summaryrefslogtreecommitdiffstats
path: root/fs/f2fs/segment.h
blob: 5c7ed0442d6e25dd08caa73efb4a506ecfd2d894 (plain)
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
// SPDX-License-Identifier: GPL-2.0
/*
 * fs/f2fs/segment.h
 *
 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
 *             http://www.samsung.com/
 */
#include <linux/blkdev.h>
#include <linux/backing-dev.h>

/* constant macro */
#define NULL_SEGNO			((unsigned int)(~0))
#define NULL_SECNO			((unsigned int)(~0))

#define DEF_RECLAIM_PREFREE_SEGMENTS	5	/* 5% over total segments */
#define DEF_MAX_RECLAIM_PREFREE_SEGMENTS	4096	/* 8GB in maximum */

#define F2FS_MIN_SEGMENTS	9 /* SB + 2 (CP + SIT + NAT) + SSA + MAIN */

/* L: Logical segment # in volume, R: Relative segment # in main area */
#define GET_L2R_SEGNO(free_i, segno)	((segno) - (free_i)->start_segno)
#define GET_R2L_SEGNO(free_i, segno)	((segno) + (free_i)->start_segno)

#define IS_DATASEG(t)	((t) <= CURSEG_COLD_DATA)
#define IS_NODESEG(t)	((t) >= CURSEG_HOT_NODE)

#define IS_HOT(t)	((t) == CURSEG_HOT_NODE || (t) == CURSEG_HOT_DATA)
#define IS_WARM(t)	((t) == CURSEG_WARM_NODE || (t) == CURSEG_WARM_DATA)
#define IS_COLD(t)	((t) == CURSEG_COLD_NODE || (t) == CURSEG_COLD_DATA)

#define IS_CURSEG(sbi, seg)						\
	(((seg) == CURSEG_I(sbi, CURSEG_HOT_DATA)->segno) ||	\
	 ((seg) == CURSEG_I(sbi, CURSEG_WARM_DATA)->segno) ||	\
	 ((seg) == CURSEG_I(sbi, CURSEG_COLD_DATA)->segno) ||	\
	 ((seg) == CURSEG_I(sbi, CURSEG_HOT_NODE)->segno) ||	\
	 ((seg) == CURSEG_I(sbi, CURSEG_WARM_NODE)->segno) ||	\
	 ((seg) == CURSEG_I(sbi, CURSEG_COLD_NODE)->segno))

#define IS_CURSEC(sbi, secno)						\
	(((secno) == CURSEG_I(sbi, CURSEG_HOT_DATA)->segno /		\
	  (sbi)->segs_per_sec) ||	\
	 ((secno) == CURSEG_I(sbi, CURSEG_WARM_DATA)->segno /		\
	  (sbi)->segs_per_sec) ||	\
	 ((secno) == CURSEG_I(sbi, CURSEG_COLD_DATA)->segno /		\
	  (sbi)->segs_per_sec) ||	\
	 ((secno) == CURSEG_I(sbi, CURSEG_HOT_NODE)->segno /		\
	  (sbi)->segs_per_sec) ||	\
	 ((secno) == CURSEG_I(sbi, CURSEG_WARM_NODE)->segno /		\
	  (sbi)->segs_per_sec) ||	\
	 ((secno) == CURSEG_I(sbi, CURSEG_COLD_NODE)->segno /		\
	  (sbi)->segs_per_sec))	\

#define MAIN_BLKADDR(sbi)						\
	(SM_I(sbi) ? SM_I(sbi)->main_blkaddr : 				\
		le32_to_cpu(F2FS_RAW_SUPER(sbi)->main_blkaddr))
#define SEG0_BLKADDR(sbi)						\
	(SM_I(sbi) ? SM_I(sbi)->seg0_blkaddr : 				\
		le32_to_cpu(F2FS_RAW_SUPER(sbi)->segment0_blkaddr))

#define MAIN_SEGS(sbi)	(SM_I(sbi)->main_segments)
#define MAIN_SECS(sbi)	((sbi)->total_sections)

#define TOTAL_SEGS(sbi)							\
	(SM_I(sbi) ? SM_I(sbi)->segment_count : 				\
		le32_to_cpu(F2FS_RAW_SUPER(sbi)->segment_count))
#define TOTAL_BLKS(sbi)	(TOTAL_SEGS(sbi) << (sbi)->log_blocks_per_seg)

#define MAX_BLKADDR(sbi)	(SEG0_BLKADDR(sbi) + TOTAL_BLKS(sbi))
#define SEGMENT_SIZE(sbi)	(1ULL << ((sbi)->log_blocksize +	\
					(sbi)->log_blocks_per_seg))

#define START_BLOCK(sbi, segno)	(SEG0_BLKADDR(sbi) +			\
	 (GET_R2L_SEGNO(FREE_I(sbi), segno) << (sbi)->log_blocks_per_seg))

#define NEXT_FREE_BLKADDR(sbi, curseg)					\
	(START_BLOCK(sbi, (curseg)->segno) + (curseg)->next_blkoff)

#define GET_SEGOFF_FROM_SEG0(sbi, blk_addr)	((blk_addr) - SEG0_BLKADDR(sbi))
#define GET_SEGNO_FROM_SEG0(sbi, blk_addr)				\
	(GET_SEGOFF_FROM_SEG0(sbi, blk_addr) >> (sbi)->log_blocks_per_seg)
#define GET_BLKOFF_FROM_SEG0(sbi, blk_addr)				\
	(GET_SEGOFF_FROM_SEG0(sbi, blk_addr) & ((sbi)->blocks_per_seg - 1))

#define GET_SEGNO(sbi, blk_addr)					\
	((!is_valid_data_blkaddr(sbi, blk_addr)) ?			\
	NULL_SEGNO : GET_L2R_SEGNO(FREE_I(sbi),			\
		GET_SEGNO_FROM_SEG0(sbi, blk_addr)))
#define BLKS_PER_SEC(sbi)					\
	((sbi)->segs_per_sec * (sbi)->blocks_per_seg)
#define GET_SEC_FROM_SEG(sbi, segno)				\
	((segno) / (sbi)->segs_per_sec)
#define GET_SEG_FROM_SEC(sbi, secno)				\
	((secno) * (sbi)->segs_per_sec)
#define GET_ZONE_FROM_SEC(sbi, secno)				\
	((secno) / (sbi)->secs_per_zone)
#define GET_ZONE_FROM_SEG(sbi, segno)				\
	GET_ZONE_FROM_SEC(sbi, GET_SEC_FROM_SEG(sbi, segno))

#define GET_SUM_BLOCK(sbi, segno)				\
	((sbi)->sm_info->ssa_blkaddr + (segno))

#define GET_SUM_TYPE(footer) ((footer)->entry_type)
#define SET_SUM_TYPE(footer, type) ((footer)->entry_type = (type))

#define SIT_ENTRY_OFFSET(sit_i, segno)					\
	((segno) % (sit_i)->sents_per_block)
#define SIT_BLOCK_OFFSET(segno)					\
	((segno) / SIT_ENTRY_PER_BLOCK)
#define	START_SEGNO(segno)		\
	(SIT_BLOCK_OFFSET(segno) * SIT_ENTRY_PER_BLOCK)
#define SIT_BLK_CNT(sbi)			\
	((MAIN_SEGS(sbi) + SIT_ENTRY_PER_BLOCK - 1) / SIT_ENTRY_PER_BLOCK)
#define f2fs_bitmap_size(nr)			\
	(BITS_TO_LONGS(nr) * sizeof(unsigned long))

#define SECTOR_FROM_BLOCK(blk_addr)					\
	(((sector_t)blk_addr) << F2FS_LOG_SECTORS_PER_BLOCK)
#define SECTOR_TO_BLOCK(sectors)					\
	((sectors) >> F2FS_LOG_SECTORS_PER_BLOCK)

/*
 * indicate a block allocation direction: RIGHT and LEFT.
 * RIGHT means allocating new sections towards the end of volume.
 * LEFT means the opposite direction.
 */
enum {
	ALLOC_RIGHT = 0,
	ALLOC_LEFT
};

/*
 * In the victim_sel_policy->alloc_mode, there are two block allocation modes.
 * LFS writes data sequentially with cleaning operations.
 * SSR (Slack Space Recycle) reuses obsolete space without cleaning operations.
 */
enum {
	LFS = 0,
	SSR
};

/*
 * In the victim_sel_policy->gc_mode, there are two gc, aka cleaning, modes.
 * GC_CB is based on cost-benefit algorithm.
 * GC_GREEDY is based on greedy algorithm.
 */
enum {
	GC_CB = 0,
	GC_GREEDY,
	ALLOC_NEXT,
	FLUSH_DEVICE,
	MAX_GC_POLICY,
};

/*
 * BG_GC means the background cleaning job.
 * FG_GC means the on-demand cleaning job.
 * FORCE_FG_GC means on-demand cleaning job in background.
 */
enum {
	BG_GC = 0,
	FG_GC,
	FORCE_FG_GC,
};

/* for a function parameter to select a victim segment */
struct victim_sel_policy {
	int alloc_mode;			/* LFS or SSR */
	int gc_mode;			/* GC_CB or GC_GREEDY */
	unsigned long *dirty_segmap;	/* dirty segment bitmap */
	unsigned int max_search;	/* maximum # of segments to search */
	unsigned int offset;		/* last scanned bitmap offset */
	unsigned int ofs_unit;		/* bitmap search unit */
	unsigned int min_cost;		/* minimum cost */
	unsigned int min_segno;		/* segment # having min. cost */
};

struct seg_entry {
	unsigned int type:6;		/* segment type like CURSEG_XXX_TYPE */
	unsigned int valid_blocks:10;	/* # of valid blocks */
	unsigned int ckpt_valid_blocks:10;	/* # of valid blocks last cp */
	unsigned int padding:6;		/* padding */
	unsigned char *cur_valid_map;	/* validity bitmap of blocks */
#ifdef CONFIG_F2FS_CHECK_FS
	unsigned char *cur_valid_map_mir;	/* mirror of current valid bitmap */
#endif
	/*
	 * # of valid blocks and the validity bitmap stored in the the last
	 * checkpoint pack. This information is used by the SSR mode.
	 */
	unsigned char *ckpt_valid_map;	/* validity bitmap of blocks last cp */
	unsigned char *discard_map;
	unsigned long long mtime;	/* modification time of the segment */
};

struct sec_entry {
	unsigned int valid_blocks;	/* # of valid blocks in a section */
};

struct segment_allocation {
	void (*allocate_segment)(struct f2fs_sb_info *, int, bool);
};

/*
 * this value is set in page as a private data which indicate that
 * the page is atomically written, and it is in inmem_pages list.
 */
#define ATOMIC_WRITTEN_PAGE		((unsigned long)-1)
#define DUMMY_WRITTEN_PAGE		((unsigned long)-2)

#define IS_ATOMIC_WRITTEN_PAGE(page)			\
		(page_private(page) == (unsigned long)ATOMIC_WRITTEN_PAGE)
#define IS_DUMMY_WRITTEN_PAGE(page)			\
		(page_private(page) == (unsigned long)DUMMY_WRITTEN_PAGE)

#define MAX_SKIP_GC_COUNT			16

struct inmem_pages {
	struct list_head list;
	struct page *page;
	block_t old_addr;		/* for revoking when fail to commit */
};

struct sit_info {
	const struct segment_allocation *s_ops;

	block_t sit_base_addr;		/* start block address of SIT area */
	block_t sit_blocks;		/* # of blocks used by SIT area */
	block_t written_valid_blocks;	/* # of valid blocks in main area */
	char *sit_bitmap;		/* SIT bitmap pointer */
#ifdef CONFIG_F2FS_CHECK_FS
	char *sit_bitmap_mir;		/* SIT bitmap mirror */
#endif
	unsigned int bitmap_size;	/* SIT bitmap size */

	unsigned long *tmp_map;			/* bitmap for temporal use */
	unsigned long *dirty_sentries_bitmap;	/* bitmap for dirty sentries */
	unsigned int dirty_sentries;		/* # of dirty sentries */
	unsigned int sents_per_block;		/* # of SIT entries per block */
	struct rw_semaphore sentry_lock;	/* to protect SIT cache */
	struct seg_entry *sentries;		/* SIT segment-level cache */
	struct sec_entry *sec_entries;		/* SIT section-level cache */

	/* for cost-benefit algorithm in cleaning procedure */
	unsigned long long elapsed_time;	/* elapsed time after mount */
	unsigned long long mounted_time;	/* mount time */
	unsigned long long min_mtime;		/* min. modification time */
	unsigned long long max_mtime;		/* max. modification time */

	unsigned int last_victim[MAX_GC_POLICY]; /* last victim segment # */
};

struct free_segmap_info {
	unsigned int start_segno;	/* start segment number logically */
	unsigned int free_segments;	/* # of free segments */
	unsigned int free_sections;	/* # of free sections */
	spinlock_t segmap_lock;		/* free segmap lock */
	unsigned long *free_segmap;	/* free segment bitmap */
	unsigned long *free_secmap;	/* free section bitmap */
};

/* Notice: The order of dirty type is same with CURSEG_XXX in f2fs.h */
enum dirty_type {
	DIRTY_HOT_DATA,		/* dirty segments assigned as hot data logs */
	DIRTY_WARM_DATA,	/* dirty segments assigned as warm data logs */
	DIRTY_COLD_DATA,	/* dirty segments assigned as cold data logs */
	DIRTY_HOT_NODE,		/* dirty segments assigned as hot node logs */
	DIRTY_WARM_NODE,	/* dirty segments assigned as warm node logs */
	DIRTY_COLD_NODE,	/* dirty segments assigned as cold node logs */
	DIRTY,			/* to count # of dirty segments */
	PRE,			/* to count # of entirely obsolete segments */
	NR_DIRTY_TYPE
};

struct dirty_seglist_info {
	const struct victim_selection *v_ops;	/* victim selction operation */
	unsigned long *dirty_segmap[NR_DIRTY_TYPE];
	struct mutex seglist_lock;		/* lock for segment bitmaps */
	int nr_dirty[NR_DIRTY_TYPE];		/* # of dirty segments */
	unsigned long *victim_secmap;		/* background GC victims */
};

/* victim selection function for cleaning and SSR */
struct victim_selection {
	int (*get_victim)(struct f2fs_sb_info *, unsigned int *,
							int, int, char);
};

/* for active log information */
struct curseg_info {
	struct mutex curseg_mutex;		/* lock for consistency */
	struct f2fs_summary_block *sum_blk;	/* cached summary block */
	struct rw_semaphore journal_rwsem;	/* protect journal area */
	struct f2fs_journal *journal;		/* cached journal info */
	unsigned char alloc_type;		/* current allocation type */
	unsigned int segno;			/* current segment number */
	unsigned short next_blkoff;		/* next block offset to write */
	unsigned int zone;			/* current zone number */
	unsigned int next_segno;		/* preallocated segment */
};

struct sit_entry_set {
	struct list_head set_list;	/* link with all sit sets */
	unsigned int start_segno;	/* start segno of sits in set */
	unsigned int entry_cnt;		/* the # of sit entries in set */
};

/*
 * inline functions
 */
static inline struct curseg_info *CURSEG_I(struct f2fs_sb_info *sbi, int type)
{
	return (struct curseg_info *)(SM_I(sbi)->curseg_array + type);
}

static inline struct seg_entry *get_seg_entry(struct f2fs_sb_info *sbi,
						unsigned int segno)
{
	struct sit_info *sit_i = SIT_I(sbi);
	return &sit_i->sentries[segno];
}

static inline struct sec_entry *get_sec_entry(struct f2fs_sb_info *sbi,
						unsigned int segno)
{
	struct sit_info *sit_i = SIT_I(sbi);
	return &sit_i->sec_entries[GET_SEC_FROM_SEG(sbi, segno)];
}

static inline unsigned int get_valid_blocks(struct f2fs_sb_info *sbi,
				unsigned int segno, bool use_section)
{
	/*
	 * In order to get # of valid blocks in a section instantly from many
	 * segments, f2fs manages two counting structures separately.
	 */
	if (use_section && __is_large_section(sbi))
		return get_sec_entry(sbi, segno)->valid_blocks;
	else
		return get_seg_entry(sbi, segno)->valid_blocks;
}

static inline unsigned int get_ckpt_valid_blocks(struct f2fs_sb_info *sbi,
				unsigned int segno)
{
	return get_seg_entry(sbi, segno)->ckpt_valid_blocks;
}

static inline void seg_info_from_raw_sit(struct seg_entry *se,
					struct f2fs_sit_entry *rs)
{
	se->valid_blocks = GET_SIT_VBLOCKS(rs);
	se->ckpt_valid_blocks = GET_SIT_VBLOCKS(rs);
	memcpy(se->cur_valid_map, rs->valid_map, SIT_VBLOCK_MAP_SIZE);
	memcpy(se->ckpt_valid_map, rs->valid_map, SIT_VBLOCK_MAP_SIZE);
#ifdef CONFIG_F2FS_CHECK_FS
	memcpy(se->cur_valid_map_mir, rs->valid_map, SIT_VBLOCK_MAP_SIZE);
#endif
	se->type = GET_SIT_TYPE(rs);
	se->mtime = le64_to_cpu(rs->mtime);
}

static inline void __seg_info_to_raw_sit(struct seg_entry *se,
					struct f2fs_sit_entry *rs)
{
	unsigned short raw_vblocks = (se->type << SIT_VBLOCKS_SHIFT) |
					se->valid_blocks;
	rs->vblocks = cpu_to_le16(raw_vblocks);
	memcpy(rs->valid_map, se->cur_valid_map, SIT_VBLOCK_MAP_SIZE);
	rs->mtime = cpu_to_le64(se->mtime);
}

static inline void seg_info_to_sit_page(struct f2fs_sb_info *sbi,
				struct page *page, unsigned int start)
{
	struct f2fs_sit_block *raw_sit;
	struct seg_entry *se;
	struct f2fs_sit_entry *rs;
	unsigned int end = min(start + SIT_ENTRY_PER_BLOCK,
					(unsigned long)MAIN_SEGS(sbi));
	int i;

	raw_sit = (struct f2fs_sit_block *)page_address(page);
	memset(raw_sit, 0, PAGE_SIZE);
	for (i = 0; i < end - start; i++) {
		rs = &raw_sit->entries[i];
		se = get_seg_entry(sbi, start + i);
		__seg_info_to_raw_sit(se, rs);
	}
}

static inline void seg_info_to_raw_sit(struct seg_entry *se,
					struct f2fs_sit_entry *rs)
{
	__seg_info_to_raw_sit(se, rs);

	memcpy(se->ckpt_valid_map, rs->valid_map, SIT_VBLOCK_MAP_SIZE);
	se->ckpt_valid_blocks = se->valid_blocks;
}

static inline unsigned int find_next_inuse(struct free_segmap_info *free_i,
		unsigned int max, unsigned int segno)
{
	unsigned int ret;
	spin_lock(&free_i->segmap_lock);
	ret = find_next_bit(free_i->free_segmap, max, segno);
	spin_unlock(&free_i->segmap_lock);
	return ret;
}

static inline void __set_free(struct f2fs_sb_info *sbi, unsigned int segno)
{
	struct free_segmap_info *free_i = FREE_I(sbi);
	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
	unsigned int start_segno = GET_SEG_FROM_SEC(sbi, secno);
	unsigned int next;

	spin_lock(&free_i->segmap_lock);
	clear_bit(segno, free_i->free_segmap);
	free_i->free_segments++;

	next = find_next_bit(free_i->free_segmap,
			start_segno + sbi->segs_per_sec, start_segno);
	if (next >= start_segno + sbi->segs_per_sec) {
		clear_bit(secno, free_i->free_secmap);
		free_i->free_sections++;
	}
	spin_unlock(&free_i->segmap_lock);
}

static inline void __set_inuse(struct f2fs_sb_info *sbi,
		unsigned int segno)
{
	struct free_segmap_info *free_i = FREE_I(sbi);
	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);

	set_bit(segno, free_i->free_segmap);
	free_i->free_segments--;
	if (!test_and_set_bit(secno, free_i->free_secmap))
		free_i->free_sections--;
}

static inline void __set_test_and_free(struct f2fs_sb_info *sbi,
		unsigned int segno)
{
	struct free_segmap_info *free_i = FREE_I(sbi);
	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
	unsigned int start_segno = GET_SEG_FROM_SEC(sbi, secno);
	unsigned int next;

	spin_lock(&free_i->segmap_lock);
	if (test_and_clear_bit(segno, free_i->free_segmap)) {
		free_i->free_segments++;

		if (IS_CURSEC(sbi, secno))
			goto skip_free;
		next = find_next_bit(free_i->free_segmap,
				start_segno + sbi->segs_per_sec, start_segno);
		if (next >= start_segno + sbi->segs_per_sec) {
			if (test_and_clear_bit(secno, free_i->free_secmap))
				free_i->free_sections++;
		}
	}
skip_free:
	spin_unlock(&free_i->segmap_lock);
}

static inline void __set_test_and_inuse(struct f2fs_sb_info *sbi,
		unsigned int segno)
{
	struct free_segmap_info *free_i = FREE_I(sbi);
	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);

	spin_lock(&free_i->segmap_lock);
	if (!test_and_set_bit(segno, free_i->free_segmap)) {
		free_i->free_segments--;
		if (!test_and_set_bit(secno, free_i->free_secmap))
			free_i->free_sections--;
	}
	spin_unlock(&free_i->segmap_lock);
}

static inline void get_sit_bitmap(struct f2fs_sb_info *sbi,
		void *dst_addr)
{
	struct sit_info *sit_i = SIT_I(sbi);

#ifdef CONFIG_F2FS_CHECK_FS
	if (memcmp(sit_i->sit_bitmap, sit_i->sit_bitmap_mir,
						sit_i->bitmap_size))
		f2fs_bug_on(sbi, 1);
#endif
	memcpy(dst_addr, sit_i->sit_bitmap, sit_i->bitmap_size);
}

static inline block_t written_block_count(struct f2fs_sb_info *sbi)
{
	return SIT_I(sbi)->written_valid_blocks;
}

static inline unsigned int free_segments(struct f2fs_sb_info *sbi)
{
	return FREE_I(sbi)->free_segments;
}

static inline int reserved_segments(struct f2fs_sb_info *sbi)
{
	return SM_I(sbi)->reserved_segments;
}

static inline unsigned int free_sections(struct f2fs_sb_info *sbi)
{
	return FREE_I(sbi)->free_sections;
}

static inline unsigned int prefree_segments(struct f2fs_sb_info *sbi)
{
	return DIRTY_I(sbi)->nr_dirty[PRE];
}

static inline unsigned int dirty_segments(struct f2fs_sb_info *sbi)
{
	return DIRTY_I(sbi)->nr_dirty[DIRTY_HOT_DATA] +
		DIRTY_I(sbi)->nr_dirty[DIRTY_WARM_DATA] +
		DIRTY_I(sbi)->nr_dirty[DIRTY_COLD_DATA] +
		DIRTY_I(sbi)->nr_dirty[DIRTY_HOT_NODE] +
		DIRTY_I(sbi)->nr_dirty[DIRTY_WARM_NODE] +
		DIRTY_I(sbi)->nr_dirty[DIRTY_COLD_NODE];
}

static inline int overprovision_segments(struct f2fs_sb_info *sbi)
{
	return SM_I(sbi)->ovp_segments;
}

static inline int reserved_sections(struct f2fs_sb_info *sbi)
{
	return GET_SEC_FROM_SEG(sbi, (unsigned int)reserved_segments(sbi));
}

static inline bool has_curseg_enough_space(struct f2fs_sb_info *sbi)
{
	unsigned int node_blocks = get_pages(sbi, F2FS_DIRTY_NODES) +
					get_pages(sbi, F2FS_DIRTY_DENTS);
	unsigned int dent_blocks = get_pages(sbi, F2FS_DIRTY_DENTS);
	unsigned int segno, left_blocks;
	int i;

	/* check current node segment */
	for (i = CURSEG_HOT_NODE; i <= CURSEG_COLD_NODE; i++) {
		segno = CURSEG_I(sbi, i)->segno;
		left_blocks = sbi->blocks_per_seg -
			get_seg_entry(sbi, segno)->ckpt_valid_blocks;

		if (node_blocks > left_blocks)
			return false;
	}

	/* check current data segment */
	segno = CURSEG_I(sbi, CURSEG_HOT_DATA)->segno;
	left_blocks = sbi->blocks_per_seg -
			get_seg_entry(sbi, segno)->ckpt_valid_blocks;
	if (dent_blocks > left_blocks)
		return false;
	return true;
}

static inline bool has_not_enough_free_secs(struct f2fs_sb_info *sbi,
					int freed, int needed)
{
	int node_secs = get_blocktype_secs(sbi, F2FS_DIRTY_NODES);
	int dent_secs = get_blocktype_secs(sbi, F2FS_DIRTY_DENTS);
	int imeta_secs = get_blocktype_secs(sbi, F2FS_DIRTY_IMETA);

	if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
		return false;

	if (free_sections(sbi) + freed == reserved_sections(sbi) + needed &&
			has_curseg_enough_space(sbi))
		return false;
	return (free_sections(sbi) + freed) <=
		(node_secs + 2 * dent_secs + imeta_secs +
		reserved_sections(sbi) + needed);
}

static inline int f2fs_is_checkpoint_ready(struct f2fs_sb_info *sbi)
{
	if (likely(!is_sbi_flag_set(sbi, SBI_CP_DISABLED)))
		return 0;
	if (likely(!has_not_enough_free_secs(sbi, 0, 0)))
		return 0;
	return -ENOSPC;
}

static inline bool excess_prefree_segs(struct f2fs_sb_info *sbi)
{
	return prefree_segments(sbi) > SM_I(sbi)->rec_prefree_segments;
}

static inline int utilization(struct f2fs_sb_info *sbi)
{
	return div_u64((u64)valid_user_blocks(sbi) * 100,
					sbi->user_block_count);
}

/*
 * Sometimes f2fs may be better to drop out-of-place update policy.
 * And, users can control the policy through sysfs entries.
 * There are five policies with triggering conditions as follows.
 * F2FS_IPU_FORCE - all the time,
 * F2FS_IPU_SSR - if SSR mode is activated,
 * F2FS_IPU_UTIL - if FS utilization is over threashold,
 * F2FS_IPU_SSR_UTIL - if SSR mode is activated and FS utilization is over
 *                     threashold,
 * F2FS_IPU_FSYNC - activated in fsync path only for high performance flash
 *                     storages. IPU will be triggered only if the # of dirty
 *                     pages over min_fsync_blocks.
 * F2FS_IPUT_DISABLE - disable IPU. (=default option)
 */
#define DEF_MIN_IPU_UTIL	70
#define DEF_MIN_FSYNC_BLOCKS	8
#define DEF_MIN_HOT_BLOCKS	16

#define SMALL_VOLUME_SEGMENTS	(16 * 512)	/* 16GB */

enum {
	F2FS_IPU_FORCE,
	F2FS_IPU_SSR,
	F2FS_IPU_UTIL,
	F2FS_IPU_SSR_UTIL,
	F2FS_IPU_FSYNC,
	F2FS_IPU_ASYNC,
};

static inline unsigned int curseg_segno(struct f2fs_sb_info *sbi,
		int type)
{
	struct curseg_info *curseg = CURSEG_I(sbi, type);
	return curseg->segno;
}

static inline unsigned char curseg_alloc_type(struct f2fs_sb_info *sbi,
		int type)
{
	struct curseg_info *curseg = CURSEG_I(sbi, type);
	return curseg->alloc_type;
}

static inline unsigned short curseg_blkoff(struct f2fs_sb_info *sbi, int type)
{
	struct curseg_info *curseg = CURSEG_I(sbi, type);
	return curseg->next_blkoff;
}

static inline void check_seg_range(struct f2fs_sb_info *sbi, unsigned int segno)
{
	f2fs_bug_on(sbi, segno > TOTAL_SEGS(sbi) - 1);
}

static inline void verify_block_addr(struct f2fs_io_info *fio, block_t blk_addr)
{
	struct f2fs_sb_info *sbi = fio->sbi;

	if (__is_meta_io(fio))
		verify_blkaddr(sbi, blk_addr, META_GENERIC);
	else
		verify_blkaddr(sbi, blk_addr, DATA_GENERIC);
}

/*
 * Summary block is always treated as an invalid block
 */
static inline int check_block_count(struct f2fs_sb_info *sbi,
		int segno, struct f2fs_sit_entry *raw_sit)
{
#ifdef CONFIG_F2FS_CHECK_FS
	bool is_valid  = test_bit_le(0, raw_sit->valid_map) ? true : false;
	int valid_blocks = 0;
	int cur_pos = 0, next_pos;

	/* check bitmap with valid block count */
	do {
		if (is_valid) {
			next_pos = find_next_zero_bit_le(&raw_sit->valid_map,
					sbi->blocks_per_seg,
					cur_pos);
			valid_blocks += next_pos - cur_pos;
		} else
			next_pos = find_next_bit_le(&raw_sit->valid_map,
					sbi->blocks_per_seg,
					cur_pos);
		cur_pos = next_pos;
		is_valid = !is_valid;
	} while (cur_pos < sbi->blocks_per_seg);

	if (unlikely(GET_SIT_VBLOCKS(raw_sit) != valid_blocks)) {
		f2fs_msg(sbi->sb, KERN_ERR,
				"Mismatch valid blocks %d vs. %d",
					GET_SIT_VBLOCKS(raw_sit), valid_blocks);
		set_sbi_flag(sbi, SBI_NEED_FSCK);
		return -EINVAL;
	}
#endif
	/* check segment usage, and check boundary of a given segment number */
	if (unlikely(GET_SIT_VBLOCKS(raw_sit) > sbi->blocks_per_seg
					|| segno > TOTAL_SEGS(sbi) - 1)) {
		f2fs_msg(sbi->sb, KERN_ERR,
				"Wrong valid blocks %d or segno %u",
					GET_SIT_VBLOCKS(raw_sit), segno);
		set_sbi_flag(sbi, SBI_NEED_FSCK);
		return -EINVAL;
	}
	return 0;
}

static inline pgoff_t current_sit_addr(struct f2fs_sb_info *sbi,
						unsigned int start)
{
	struct sit_info *sit_i = SIT_I(sbi);
	unsigned int offset = SIT_BLOCK_OFFSET(start);
	block_t blk_addr = sit_i->sit_base_addr + offset;

	check_seg_range(sbi, start);

#ifdef CONFIG_F2FS_CHECK_FS
	if (f2fs_test_bit(offset, sit_i->sit_bitmap) !=
			f2fs_test_bit(offset, sit_i->sit_bitmap_mir))
		f2fs_bug_on(sbi, 1);
#endif

	/* calculate sit block address */
	if (f2fs_test_bit(offset, sit_i->sit_bitmap))
		blk_addr += sit_i->sit_blocks;

	return blk_addr;
}

static inline pgoff_t next_sit_addr(struct f2fs_sb_info *sbi,
						pgoff_t block_addr)
{
	struct sit_info *sit_i = SIT_I(sbi);
	block_addr -= sit_i->sit_base_addr;
	if (block_addr < sit_i->sit_blocks)
		block_addr += sit_i->sit_blocks;
	else
		block_addr -= sit_i->sit_blocks;

	return block_addr + sit_i->sit_base_addr;
}

static inline void set_to_next_sit(struct sit_info *sit_i, unsigned int start)
{
	unsigned int block_off = SIT_BLOCK_OFFSET(start);

	f2fs_change_bit(block_off, sit_i->sit_bitmap);
#ifdef CONFIG_F2FS_CHECK_FS
	f2fs_change_bit(block_off, sit_i->sit_bitmap_mir);
#endif
}

static inline unsigned long long get_mtime(struct f2fs_sb_info *sbi,
						bool base_time)
{
	struct sit_info *sit_i = SIT_I(sbi);
	time64_t diff, now = ktime_get_real_seconds();

	if (now >= sit_i->mounted_time)
		return sit_i->elapsed_time + now - sit_i->mounted_time;

	/* system time is set to the past */
	if (!base_time) {
		diff = sit_i->mounted_time - now;
		if (sit_i->elapsed_time >= diff)
			return sit_i->elapsed_time - diff;
		return 0;
	}
	return sit_i->elapsed_time;
}

static inline void set_summary(struct f2fs_summary *sum, nid_t nid,
			unsigned int ofs_in_node, unsigned char version)
{
	sum->nid = cpu_to_le32(nid);
	sum->ofs_in_node = cpu_to_le16(ofs_in_node);
	sum->version = version;
}

static inline block_t start_sum_block(struct f2fs_sb_info *sbi)
{
	return __start_cp_addr(sbi) +
		le32_to_cpu(F2FS_CKPT(sbi)->cp_pack_start_sum);
}

static inline block_t sum_blk_addr(struct f2fs_sb_info *sbi, int base, int type)
{
	return __start_cp_addr(sbi) +
		le32_to_cpu(F2FS_CKPT(sbi)->cp_pack_total_block_count)
				- (base + 1) + type;
}

static inline bool sec_usage_check(struct f2fs_sb_info *sbi, unsigned int secno)
{
	if (IS_CURSEC(sbi, secno) || (sbi->cur_victim_sec == secno))
		return true;
	return false;
}

/*
 * It is very important to gather dirty pages and write at once, so that we can
 * submit a big bio without interfering other data writes.
 * By default, 512 pages for directory data,
 * 512 pages (2MB) * 8 for nodes, and
 * 256 pages * 8 for meta are set.
 */
static inline int nr_pages_to_skip(struct f2fs_sb_info *sbi, int type)
{
	if (sbi->sb->s_bdi->wb.dirty_exceeded)
		return 0;

	if (type == DATA)
		return sbi->blocks_per_seg;
	else if (type == NODE)
		return 8 * sbi->blocks_per_seg;
	else if (type == META)
		return 8 * BIO_MAX_PAGES;
	else
		return 0;
}

/*
 * When writing pages, it'd better align nr_to_write for segment size.
 */
static inline long nr_pages_to_write(struct f2fs_sb_info *sbi, int type,
					struct writeback_control *wbc)
{
	long nr_to_write, desired;

	if (wbc->sync_mode != WB_SYNC_NONE)
		return 0;

	nr_to_write = wbc->nr_to_write;
	desired = BIO_MAX_PAGES;
	if (type == NODE)
		desired <<= 1;

	wbc->nr_to_write = desired;
	return desired - nr_to_write;
}

static inline void wake_up_discard_thread(struct f2fs_sb_info *sbi, bool force)
{
	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
	bool wakeup = false;
	int i;

	if (force)
		goto wake_up;

	mutex_lock(&dcc->cmd_lock);
	for (i = MAX_PLIST_NUM - 1; i >= 0; i--) {
		if (i + 1 < dcc->discard_granularity)
			break;
		if (!list_empty(&dcc->pend_list[i])) {
			wakeup = true;
			break;
		}
	}
	mutex_unlock(&dcc->cmd_lock);
	if (!wakeup || !is_idle(sbi, DISCARD_TIME))
		return;
wake_up:
	dcc->discard_wake = 1;
	wake_up_interruptible_all(&dcc->discard_wait_queue);
}