segment.c revision dcdfff65276fdc6dfe5eb1d0aff802dfa7a95e15
1/*
2 * fs/f2fs/segment.c
3 *
4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 *             http://www.samsung.com/
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11#include <linux/fs.h>
12#include <linux/f2fs_fs.h>
13#include <linux/bio.h>
14#include <linux/blkdev.h>
15#include <linux/prefetch.h>
16#include <linux/vmalloc.h>
17
18#include "f2fs.h"
19#include "segment.h"
20#include "node.h"
21#include <trace/events/f2fs.h>
22
23/*
24 * This function balances dirty node and dentry pages.
25 * In addition, it controls garbage collection.
26 */
27void f2fs_balance_fs(struct f2fs_sb_info *sbi)
28{
29	/*
30	 * We should do GC or end up with checkpoint, if there are so many dirty
31	 * dir/node pages without enough free segments.
32	 */
33	if (has_not_enough_free_secs(sbi, 0)) {
34		mutex_lock(&sbi->gc_mutex);
35		f2fs_gc(sbi);
36	}
37}
38
39static void __locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
40		enum dirty_type dirty_type)
41{
42	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
43
44	/* need not be added */
45	if (IS_CURSEG(sbi, segno))
46		return;
47
48	if (!test_and_set_bit(segno, dirty_i->dirty_segmap[dirty_type]))
49		dirty_i->nr_dirty[dirty_type]++;
50
51	if (dirty_type == DIRTY) {
52		struct seg_entry *sentry = get_seg_entry(sbi, segno);
53		enum dirty_type t = DIRTY_HOT_DATA;
54
55		dirty_type = sentry->type;
56
57		if (!test_and_set_bit(segno, dirty_i->dirty_segmap[dirty_type]))
58			dirty_i->nr_dirty[dirty_type]++;
59
60		/* Only one bitmap should be set */
61		for (; t <= DIRTY_COLD_NODE; t++) {
62			if (t == dirty_type)
63				continue;
64			if (test_and_clear_bit(segno, dirty_i->dirty_segmap[t]))
65				dirty_i->nr_dirty[t]--;
66		}
67	}
68}
69
70static void __remove_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
71		enum dirty_type dirty_type)
72{
73	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
74
75	if (test_and_clear_bit(segno, dirty_i->dirty_segmap[dirty_type]))
76		dirty_i->nr_dirty[dirty_type]--;
77
78	if (dirty_type == DIRTY) {
79		enum dirty_type t = DIRTY_HOT_DATA;
80
81		/* clear its dirty bitmap */
82		for (; t <= DIRTY_COLD_NODE; t++) {
83			if (test_and_clear_bit(segno,
84						dirty_i->dirty_segmap[t])) {
85				dirty_i->nr_dirty[t]--;
86				break;
87			}
88		}
89
90		if (get_valid_blocks(sbi, segno, sbi->segs_per_sec) == 0)
91			clear_bit(GET_SECNO(sbi, segno),
92						dirty_i->victim_secmap);
93	}
94}
95
96/*
97 * Should not occur error such as -ENOMEM.
98 * Adding dirty entry into seglist is not critical operation.
99 * If a given segment is one of current working segments, it won't be added.
100 */
101static void locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno)
102{
103	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
104	unsigned short valid_blocks;
105
106	if (segno == NULL_SEGNO || IS_CURSEG(sbi, segno))
107		return;
108
109	mutex_lock(&dirty_i->seglist_lock);
110
111	valid_blocks = get_valid_blocks(sbi, segno, 0);
112
113	if (valid_blocks == 0) {
114		__locate_dirty_segment(sbi, segno, PRE);
115		__remove_dirty_segment(sbi, segno, DIRTY);
116	} else if (valid_blocks < sbi->blocks_per_seg) {
117		__locate_dirty_segment(sbi, segno, DIRTY);
118	} else {
119		/* Recovery routine with SSR needs this */
120		__remove_dirty_segment(sbi, segno, DIRTY);
121	}
122
123	mutex_unlock(&dirty_i->seglist_lock);
124}
125
126/*
127 * Should call clear_prefree_segments after checkpoint is done.
128 */
129static void set_prefree_as_free_segments(struct f2fs_sb_info *sbi)
130{
131	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
132	unsigned int segno = -1;
133	unsigned int total_segs = TOTAL_SEGS(sbi);
134
135	mutex_lock(&dirty_i->seglist_lock);
136	while (1) {
137		segno = find_next_bit(dirty_i->dirty_segmap[PRE], total_segs,
138				segno + 1);
139		if (segno >= total_segs)
140			break;
141		__set_test_and_free(sbi, segno);
142	}
143	mutex_unlock(&dirty_i->seglist_lock);
144}
145
146void clear_prefree_segments(struct f2fs_sb_info *sbi)
147{
148	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
149	unsigned int segno = -1;
150	unsigned int total_segs = TOTAL_SEGS(sbi);
151
152	mutex_lock(&dirty_i->seglist_lock);
153	while (1) {
154		segno = find_next_bit(dirty_i->dirty_segmap[PRE], total_segs,
155				segno + 1);
156		if (segno >= total_segs)
157			break;
158
159		if (test_and_clear_bit(segno, dirty_i->dirty_segmap[PRE]))
160			dirty_i->nr_dirty[PRE]--;
161
162		/* Let's use trim */
163		if (test_opt(sbi, DISCARD))
164			blkdev_issue_discard(sbi->sb->s_bdev,
165					START_BLOCK(sbi, segno) <<
166					sbi->log_sectors_per_block,
167					1 << (sbi->log_sectors_per_block +
168						sbi->log_blocks_per_seg),
169					GFP_NOFS, 0);
170	}
171	mutex_unlock(&dirty_i->seglist_lock);
172}
173
174static void __mark_sit_entry_dirty(struct f2fs_sb_info *sbi, unsigned int segno)
175{
176	struct sit_info *sit_i = SIT_I(sbi);
177	if (!__test_and_set_bit(segno, sit_i->dirty_sentries_bitmap))
178		sit_i->dirty_sentries++;
179}
180
181static void __set_sit_entry_type(struct f2fs_sb_info *sbi, int type,
182					unsigned int segno, int modified)
183{
184	struct seg_entry *se = get_seg_entry(sbi, segno);
185	se->type = type;
186	if (modified)
187		__mark_sit_entry_dirty(sbi, segno);
188}
189
190static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
191{
192	struct seg_entry *se;
193	unsigned int segno, offset;
194	long int new_vblocks;
195
196	segno = GET_SEGNO(sbi, blkaddr);
197
198	se = get_seg_entry(sbi, segno);
199	new_vblocks = se->valid_blocks + del;
200	offset = GET_SEGOFF_FROM_SEG0(sbi, blkaddr) & (sbi->blocks_per_seg - 1);
201
202	BUG_ON((new_vblocks >> (sizeof(unsigned short) << 3) ||
203				(new_vblocks > sbi->blocks_per_seg)));
204
205	se->valid_blocks = new_vblocks;
206	se->mtime = get_mtime(sbi);
207	SIT_I(sbi)->max_mtime = se->mtime;
208
209	/* Update valid block bitmap */
210	if (del > 0) {
211		if (f2fs_set_bit(offset, se->cur_valid_map))
212			BUG();
213	} else {
214		if (!f2fs_clear_bit(offset, se->cur_valid_map))
215			BUG();
216	}
217	if (!f2fs_test_bit(offset, se->ckpt_valid_map))
218		se->ckpt_valid_blocks += del;
219
220	__mark_sit_entry_dirty(sbi, segno);
221
222	/* update total number of valid blocks to be written in ckpt area */
223	SIT_I(sbi)->written_valid_blocks += del;
224
225	if (sbi->segs_per_sec > 1)
226		get_sec_entry(sbi, segno)->valid_blocks += del;
227}
228
229static void refresh_sit_entry(struct f2fs_sb_info *sbi,
230			block_t old_blkaddr, block_t new_blkaddr)
231{
232	update_sit_entry(sbi, new_blkaddr, 1);
233	if (GET_SEGNO(sbi, old_blkaddr) != NULL_SEGNO)
234		update_sit_entry(sbi, old_blkaddr, -1);
235}
236
237void invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr)
238{
239	unsigned int segno = GET_SEGNO(sbi, addr);
240	struct sit_info *sit_i = SIT_I(sbi);
241
242	BUG_ON(addr == NULL_ADDR);
243	if (addr == NEW_ADDR)
244		return;
245
246	/* add it into sit main buffer */
247	mutex_lock(&sit_i->sentry_lock);
248
249	update_sit_entry(sbi, addr, -1);
250
251	/* add it into dirty seglist */
252	locate_dirty_segment(sbi, segno);
253
254	mutex_unlock(&sit_i->sentry_lock);
255}
256
257/*
258 * This function should be resided under the curseg_mutex lock
259 */
260static void __add_sum_entry(struct f2fs_sb_info *sbi, int type,
261					struct f2fs_summary *sum)
262{
263	struct curseg_info *curseg = CURSEG_I(sbi, type);
264	void *addr = curseg->sum_blk;
265	addr += curseg->next_blkoff * sizeof(struct f2fs_summary);
266	memcpy(addr, sum, sizeof(struct f2fs_summary));
267}
268
269/*
270 * Calculate the number of current summary pages for writing
271 */
272int npages_for_summary_flush(struct f2fs_sb_info *sbi)
273{
274	int total_size_bytes = 0;
275	int valid_sum_count = 0;
276	int i, sum_space;
277
278	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
279		if (sbi->ckpt->alloc_type[i] == SSR)
280			valid_sum_count += sbi->blocks_per_seg;
281		else
282			valid_sum_count += curseg_blkoff(sbi, i);
283	}
284
285	total_size_bytes = valid_sum_count * (SUMMARY_SIZE + 1)
286			+ sizeof(struct nat_journal) + 2
287			+ sizeof(struct sit_journal) + 2;
288	sum_space = PAGE_CACHE_SIZE - SUM_FOOTER_SIZE;
289	if (total_size_bytes < sum_space)
290		return 1;
291	else if (total_size_bytes < 2 * sum_space)
292		return 2;
293	return 3;
294}
295
296/*
297 * Caller should put this summary page
298 */
299struct page *get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno)
300{
301	return get_meta_page(sbi, GET_SUM_BLOCK(sbi, segno));
302}
303
304static void write_sum_page(struct f2fs_sb_info *sbi,
305			struct f2fs_summary_block *sum_blk, block_t blk_addr)
306{
307	struct page *page = grab_meta_page(sbi, blk_addr);
308	void *kaddr = page_address(page);
309	memcpy(kaddr, sum_blk, PAGE_CACHE_SIZE);
310	set_page_dirty(page);
311	f2fs_put_page(page, 1);
312}
313
314static int is_next_segment_free(struct f2fs_sb_info *sbi, int type)
315{
316	struct curseg_info *curseg = CURSEG_I(sbi, type);
317	unsigned int segno = curseg->segno + 1;
318	struct free_segmap_info *free_i = FREE_I(sbi);
319
320	if (segno < TOTAL_SEGS(sbi) && segno % sbi->segs_per_sec)
321		return !test_bit(segno, free_i->free_segmap);
322	return 0;
323}
324
325/*
326 * Find a new segment from the free segments bitmap to right order
327 * This function should be returned with success, otherwise BUG
328 */
329static void get_new_segment(struct f2fs_sb_info *sbi,
330			unsigned int *newseg, bool new_sec, int dir)
331{
332	struct free_segmap_info *free_i = FREE_I(sbi);
333	unsigned int segno, secno, zoneno;
334	unsigned int total_zones = TOTAL_SECS(sbi) / sbi->secs_per_zone;
335	unsigned int hint = *newseg / sbi->segs_per_sec;
336	unsigned int old_zoneno = GET_ZONENO_FROM_SEGNO(sbi, *newseg);
337	unsigned int left_start = hint;
338	bool init = true;
339	int go_left = 0;
340	int i;
341
342	write_lock(&free_i->segmap_lock);
343
344	if (!new_sec && ((*newseg + 1) % sbi->segs_per_sec)) {
345		segno = find_next_zero_bit(free_i->free_segmap,
346					TOTAL_SEGS(sbi), *newseg + 1);
347		if (segno - *newseg < sbi->segs_per_sec -
348					(*newseg % sbi->segs_per_sec))
349			goto got_it;
350	}
351find_other_zone:
352	secno = find_next_zero_bit(free_i->free_secmap, TOTAL_SECS(sbi), hint);
353	if (secno >= TOTAL_SECS(sbi)) {
354		if (dir == ALLOC_RIGHT) {
355			secno = find_next_zero_bit(free_i->free_secmap,
356							TOTAL_SECS(sbi), 0);
357			BUG_ON(secno >= TOTAL_SECS(sbi));
358		} else {
359			go_left = 1;
360			left_start = hint - 1;
361		}
362	}
363	if (go_left == 0)
364		goto skip_left;
365
366	while (test_bit(left_start, free_i->free_secmap)) {
367		if (left_start > 0) {
368			left_start--;
369			continue;
370		}
371		left_start = find_next_zero_bit(free_i->free_secmap,
372							TOTAL_SECS(sbi), 0);
373		BUG_ON(left_start >= TOTAL_SECS(sbi));
374		break;
375	}
376	secno = left_start;
377skip_left:
378	hint = secno;
379	segno = secno * sbi->segs_per_sec;
380	zoneno = secno / sbi->secs_per_zone;
381
382	/* give up on finding another zone */
383	if (!init)
384		goto got_it;
385	if (sbi->secs_per_zone == 1)
386		goto got_it;
387	if (zoneno == old_zoneno)
388		goto got_it;
389	if (dir == ALLOC_LEFT) {
390		if (!go_left && zoneno + 1 >= total_zones)
391			goto got_it;
392		if (go_left && zoneno == 0)
393			goto got_it;
394	}
395	for (i = 0; i < NR_CURSEG_TYPE; i++)
396		if (CURSEG_I(sbi, i)->zone == zoneno)
397			break;
398
399	if (i < NR_CURSEG_TYPE) {
400		/* zone is in user, try another */
401		if (go_left)
402			hint = zoneno * sbi->secs_per_zone - 1;
403		else if (zoneno + 1 >= total_zones)
404			hint = 0;
405		else
406			hint = (zoneno + 1) * sbi->secs_per_zone;
407		init = false;
408		goto find_other_zone;
409	}
410got_it:
411	/* set it as dirty segment in free segmap */
412	BUG_ON(test_bit(segno, free_i->free_segmap));
413	__set_inuse(sbi, segno);
414	*newseg = segno;
415	write_unlock(&free_i->segmap_lock);
416}
417
418static void reset_curseg(struct f2fs_sb_info *sbi, int type, int modified)
419{
420	struct curseg_info *curseg = CURSEG_I(sbi, type);
421	struct summary_footer *sum_footer;
422
423	curseg->segno = curseg->next_segno;
424	curseg->zone = GET_ZONENO_FROM_SEGNO(sbi, curseg->segno);
425	curseg->next_blkoff = 0;
426	curseg->next_segno = NULL_SEGNO;
427
428	sum_footer = &(curseg->sum_blk->footer);
429	memset(sum_footer, 0, sizeof(struct summary_footer));
430	if (IS_DATASEG(type))
431		SET_SUM_TYPE(sum_footer, SUM_TYPE_DATA);
432	if (IS_NODESEG(type))
433		SET_SUM_TYPE(sum_footer, SUM_TYPE_NODE);
434	__set_sit_entry_type(sbi, type, curseg->segno, modified);
435}
436
437/*
438 * Allocate a current working segment.
439 * This function always allocates a free segment in LFS manner.
440 */
441static void new_curseg(struct f2fs_sb_info *sbi, int type, bool new_sec)
442{
443	struct curseg_info *curseg = CURSEG_I(sbi, type);
444	unsigned int segno = curseg->segno;
445	int dir = ALLOC_LEFT;
446
447	write_sum_page(sbi, curseg->sum_blk,
448				GET_SUM_BLOCK(sbi, segno));
449	if (type == CURSEG_WARM_DATA || type == CURSEG_COLD_DATA)
450		dir = ALLOC_RIGHT;
451
452	if (test_opt(sbi, NOHEAP))
453		dir = ALLOC_RIGHT;
454
455	get_new_segment(sbi, &segno, new_sec, dir);
456	curseg->next_segno = segno;
457	reset_curseg(sbi, type, 1);
458	curseg->alloc_type = LFS;
459}
460
461static void __next_free_blkoff(struct f2fs_sb_info *sbi,
462			struct curseg_info *seg, block_t start)
463{
464	struct seg_entry *se = get_seg_entry(sbi, seg->segno);
465	block_t ofs;
466	for (ofs = start; ofs < sbi->blocks_per_seg; ofs++) {
467		if (!f2fs_test_bit(ofs, se->ckpt_valid_map)
468			&& !f2fs_test_bit(ofs, se->cur_valid_map))
469			break;
470	}
471	seg->next_blkoff = ofs;
472}
473
474/*
475 * If a segment is written by LFS manner, next block offset is just obtained
476 * by increasing the current block offset. However, if a segment is written by
477 * SSR manner, next block offset obtained by calling __next_free_blkoff
478 */
479static void __refresh_next_blkoff(struct f2fs_sb_info *sbi,
480				struct curseg_info *seg)
481{
482	if (seg->alloc_type == SSR)
483		__next_free_blkoff(sbi, seg, seg->next_blkoff + 1);
484	else
485		seg->next_blkoff++;
486}
487
488/*
489 * This function always allocates a used segment (from dirty seglist) by SSR
490 * manner, so it should recover the existing segment information of valid blocks
491 */
492static void change_curseg(struct f2fs_sb_info *sbi, int type, bool reuse)
493{
494	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
495	struct curseg_info *curseg = CURSEG_I(sbi, type);
496	unsigned int new_segno = curseg->next_segno;
497	struct f2fs_summary_block *sum_node;
498	struct page *sum_page;
499
500	write_sum_page(sbi, curseg->sum_blk,
501				GET_SUM_BLOCK(sbi, curseg->segno));
502	__set_test_and_inuse(sbi, new_segno);
503
504	mutex_lock(&dirty_i->seglist_lock);
505	__remove_dirty_segment(sbi, new_segno, PRE);
506	__remove_dirty_segment(sbi, new_segno, DIRTY);
507	mutex_unlock(&dirty_i->seglist_lock);
508
509	reset_curseg(sbi, type, 1);
510	curseg->alloc_type = SSR;
511	__next_free_blkoff(sbi, curseg, 0);
512
513	if (reuse) {
514		sum_page = get_sum_page(sbi, new_segno);
515		sum_node = (struct f2fs_summary_block *)page_address(sum_page);
516		memcpy(curseg->sum_blk, sum_node, SUM_ENTRY_SIZE);
517		f2fs_put_page(sum_page, 1);
518	}
519}
520
521static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
522{
523	struct curseg_info *curseg = CURSEG_I(sbi, type);
524	const struct victim_selection *v_ops = DIRTY_I(sbi)->v_ops;
525
526	if (IS_NODESEG(type) || !has_not_enough_free_secs(sbi, 0))
527		return v_ops->get_victim(sbi,
528				&(curseg)->next_segno, BG_GC, type, SSR);
529
530	/* For data segments, let's do SSR more intensively */
531	for (; type >= CURSEG_HOT_DATA; type--)
532		if (v_ops->get_victim(sbi, &(curseg)->next_segno,
533						BG_GC, type, SSR))
534			return 1;
535	return 0;
536}
537
538/*
539 * flush out current segment and replace it with new segment
540 * This function should be returned with success, otherwise BUG
541 */
542static void allocate_segment_by_default(struct f2fs_sb_info *sbi,
543						int type, bool force)
544{
545	struct curseg_info *curseg = CURSEG_I(sbi, type);
546
547	if (force)
548		new_curseg(sbi, type, true);
549	else if (type == CURSEG_WARM_NODE)
550		new_curseg(sbi, type, false);
551	else if (curseg->alloc_type == LFS && is_next_segment_free(sbi, type))
552		new_curseg(sbi, type, false);
553	else if (need_SSR(sbi) && get_ssr_segment(sbi, type))
554		change_curseg(sbi, type, true);
555	else
556		new_curseg(sbi, type, false);
557
558	stat_inc_seg_type(sbi, curseg);
559}
560
561void allocate_new_segments(struct f2fs_sb_info *sbi)
562{
563	struct curseg_info *curseg;
564	unsigned int old_curseg;
565	int i;
566
567	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
568		curseg = CURSEG_I(sbi, i);
569		old_curseg = curseg->segno;
570		SIT_I(sbi)->s_ops->allocate_segment(sbi, i, true);
571		locate_dirty_segment(sbi, old_curseg);
572	}
573}
574
575static const struct segment_allocation default_salloc_ops = {
576	.allocate_segment = allocate_segment_by_default,
577};
578
579static void f2fs_end_io_write(struct bio *bio, int err)
580{
581	const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
582	struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
583	struct bio_private *p = bio->bi_private;
584
585	do {
586		struct page *page = bvec->bv_page;
587
588		if (--bvec >= bio->bi_io_vec)
589			prefetchw(&bvec->bv_page->flags);
590		if (!uptodate) {
591			SetPageError(page);
592			if (page->mapping)
593				set_bit(AS_EIO, &page->mapping->flags);
594			set_ckpt_flags(p->sbi->ckpt, CP_ERROR_FLAG);
595			p->sbi->sb->s_flags |= MS_RDONLY;
596		}
597		end_page_writeback(page);
598		dec_page_count(p->sbi, F2FS_WRITEBACK);
599	} while (bvec >= bio->bi_io_vec);
600
601	if (p->is_sync)
602		complete(p->wait);
603
604	if (!get_pages(p->sbi, F2FS_WRITEBACK) && p->sbi->cp_task)
605		wake_up_process(p->sbi->cp_task);
606
607	kfree(p);
608	bio_put(bio);
609}
610
611struct bio *f2fs_bio_alloc(struct block_device *bdev, int npages)
612{
613	struct bio *bio;
614
615	/* No failure on bio allocation */
616	bio = bio_alloc(GFP_NOIO, npages);
617	bio->bi_bdev = bdev;
618	bio->bi_private = NULL;
619
620	return bio;
621}
622
623static void do_submit_bio(struct f2fs_sb_info *sbi,
624				enum page_type type, bool sync)
625{
626	int rw = sync ? WRITE_SYNC : WRITE;
627	enum page_type btype = type > META ? META : type;
628
629	if (type >= META_FLUSH)
630		rw = WRITE_FLUSH_FUA;
631
632	if (btype == META)
633		rw |= REQ_META;
634
635	if (sbi->bio[btype]) {
636		struct bio_private *p = sbi->bio[btype]->bi_private;
637		p->sbi = sbi;
638		sbi->bio[btype]->bi_end_io = f2fs_end_io_write;
639
640		trace_f2fs_do_submit_bio(sbi->sb, btype, sync, sbi->bio[btype]);
641
642		if (type == META_FLUSH) {
643			DECLARE_COMPLETION_ONSTACK(wait);
644			p->is_sync = true;
645			p->wait = &wait;
646			submit_bio(rw, sbi->bio[btype]);
647			wait_for_completion(&wait);
648		} else {
649			p->is_sync = false;
650			submit_bio(rw, sbi->bio[btype]);
651		}
652		sbi->bio[btype] = NULL;
653	}
654}
655
656void f2fs_submit_bio(struct f2fs_sb_info *sbi, enum page_type type, bool sync)
657{
658	down_write(&sbi->bio_sem);
659	do_submit_bio(sbi, type, sync);
660	up_write(&sbi->bio_sem);
661}
662
663static void submit_write_page(struct f2fs_sb_info *sbi, struct page *page,
664				block_t blk_addr, enum page_type type)
665{
666	struct block_device *bdev = sbi->sb->s_bdev;
667	int bio_blocks;
668
669	verify_block_addr(sbi, blk_addr);
670
671	down_write(&sbi->bio_sem);
672
673	inc_page_count(sbi, F2FS_WRITEBACK);
674
675	if (sbi->bio[type] && sbi->last_block_in_bio[type] != blk_addr - 1)
676		do_submit_bio(sbi, type, false);
677alloc_new:
678	if (sbi->bio[type] == NULL) {
679		struct bio_private *priv;
680retry:
681		priv = kmalloc(sizeof(struct bio_private), GFP_NOFS);
682		if (!priv) {
683			cond_resched();
684			goto retry;
685		}
686
687		bio_blocks = MAX_BIO_BLOCKS(max_hw_blocks(sbi));
688		sbi->bio[type] = f2fs_bio_alloc(bdev, bio_blocks);
689		sbi->bio[type]->bi_sector = SECTOR_FROM_BLOCK(sbi, blk_addr);
690		sbi->bio[type]->bi_private = priv;
691		/*
692		 * The end_io will be assigned at the sumbission phase.
693		 * Until then, let bio_add_page() merge consecutive IOs as much
694		 * as possible.
695		 */
696	}
697
698	if (bio_add_page(sbi->bio[type], page, PAGE_CACHE_SIZE, 0) <
699							PAGE_CACHE_SIZE) {
700		do_submit_bio(sbi, type, false);
701		goto alloc_new;
702	}
703
704	sbi->last_block_in_bio[type] = blk_addr;
705
706	up_write(&sbi->bio_sem);
707	trace_f2fs_submit_write_page(page, blk_addr, type);
708}
709
710void f2fs_wait_on_page_writeback(struct page *page,
711				enum page_type type, bool sync)
712{
713	struct f2fs_sb_info *sbi = F2FS_SB(page->mapping->host->i_sb);
714	if (PageWriteback(page)) {
715		f2fs_submit_bio(sbi, type, sync);
716		wait_on_page_writeback(page);
717	}
718}
719
720static bool __has_curseg_space(struct f2fs_sb_info *sbi, int type)
721{
722	struct curseg_info *curseg = CURSEG_I(sbi, type);
723	if (curseg->next_blkoff < sbi->blocks_per_seg)
724		return true;
725	return false;
726}
727
728static int __get_segment_type_2(struct page *page, enum page_type p_type)
729{
730	if (p_type == DATA)
731		return CURSEG_HOT_DATA;
732	else
733		return CURSEG_HOT_NODE;
734}
735
736static int __get_segment_type_4(struct page *page, enum page_type p_type)
737{
738	if (p_type == DATA) {
739		struct inode *inode = page->mapping->host;
740
741		if (S_ISDIR(inode->i_mode))
742			return CURSEG_HOT_DATA;
743		else
744			return CURSEG_COLD_DATA;
745	} else {
746		if (IS_DNODE(page) && !is_cold_node(page))
747			return CURSEG_HOT_NODE;
748		else
749			return CURSEG_COLD_NODE;
750	}
751}
752
753static int __get_segment_type_6(struct page *page, enum page_type p_type)
754{
755	if (p_type == DATA) {
756		struct inode *inode = page->mapping->host;
757
758		if (S_ISDIR(inode->i_mode))
759			return CURSEG_HOT_DATA;
760		else if (is_cold_data(page) || file_is_cold(inode))
761			return CURSEG_COLD_DATA;
762		else
763			return CURSEG_WARM_DATA;
764	} else {
765		if (IS_DNODE(page))
766			return is_cold_node(page) ? CURSEG_WARM_NODE :
767						CURSEG_HOT_NODE;
768		else
769			return CURSEG_COLD_NODE;
770	}
771}
772
773static int __get_segment_type(struct page *page, enum page_type p_type)
774{
775	struct f2fs_sb_info *sbi = F2FS_SB(page->mapping->host->i_sb);
776	switch (sbi->active_logs) {
777	case 2:
778		return __get_segment_type_2(page, p_type);
779	case 4:
780		return __get_segment_type_4(page, p_type);
781	}
782	/* NR_CURSEG_TYPE(6) logs by default */
783	BUG_ON(sbi->active_logs != NR_CURSEG_TYPE);
784	return __get_segment_type_6(page, p_type);
785}
786
787static void do_write_page(struct f2fs_sb_info *sbi, struct page *page,
788			block_t old_blkaddr, block_t *new_blkaddr,
789			struct f2fs_summary *sum, enum page_type p_type)
790{
791	struct sit_info *sit_i = SIT_I(sbi);
792	struct curseg_info *curseg;
793	unsigned int old_cursegno;
794	int type;
795
796	type = __get_segment_type(page, p_type);
797	curseg = CURSEG_I(sbi, type);
798
799	mutex_lock(&curseg->curseg_mutex);
800
801	*new_blkaddr = NEXT_FREE_BLKADDR(sbi, curseg);
802	old_cursegno = curseg->segno;
803
804	/*
805	 * __add_sum_entry should be resided under the curseg_mutex
806	 * because, this function updates a summary entry in the
807	 * current summary block.
808	 */
809	__add_sum_entry(sbi, type, sum);
810
811	mutex_lock(&sit_i->sentry_lock);
812	__refresh_next_blkoff(sbi, curseg);
813
814	stat_inc_block_count(sbi, curseg);
815
816	/*
817	 * SIT information should be updated before segment allocation,
818	 * since SSR needs latest valid block information.
819	 */
820	refresh_sit_entry(sbi, old_blkaddr, *new_blkaddr);
821
822	if (!__has_curseg_space(sbi, type))
823		sit_i->s_ops->allocate_segment(sbi, type, false);
824
825	locate_dirty_segment(sbi, old_cursegno);
826	locate_dirty_segment(sbi, GET_SEGNO(sbi, old_blkaddr));
827	mutex_unlock(&sit_i->sentry_lock);
828
829	if (p_type == NODE)
830		fill_node_footer_blkaddr(page, NEXT_FREE_BLKADDR(sbi, curseg));
831
832	/* writeout dirty page into bdev */
833	submit_write_page(sbi, page, *new_blkaddr, p_type);
834
835	mutex_unlock(&curseg->curseg_mutex);
836}
837
838void write_meta_page(struct f2fs_sb_info *sbi, struct page *page)
839{
840	set_page_writeback(page);
841	submit_write_page(sbi, page, page->index, META);
842}
843
844void write_node_page(struct f2fs_sb_info *sbi, struct page *page,
845		unsigned int nid, block_t old_blkaddr, block_t *new_blkaddr)
846{
847	struct f2fs_summary sum;
848	set_summary(&sum, nid, 0, 0);
849	do_write_page(sbi, page, old_blkaddr, new_blkaddr, &sum, NODE);
850}
851
852void write_data_page(struct inode *inode, struct page *page,
853		struct dnode_of_data *dn, block_t old_blkaddr,
854		block_t *new_blkaddr)
855{
856	struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
857	struct f2fs_summary sum;
858	struct node_info ni;
859
860	BUG_ON(old_blkaddr == NULL_ADDR);
861	get_node_info(sbi, dn->nid, &ni);
862	set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
863
864	do_write_page(sbi, page, old_blkaddr,
865			new_blkaddr, &sum, DATA);
866}
867
868void rewrite_data_page(struct f2fs_sb_info *sbi, struct page *page,
869					block_t old_blk_addr)
870{
871	submit_write_page(sbi, page, old_blk_addr, DATA);
872}
873
874void recover_data_page(struct f2fs_sb_info *sbi,
875			struct page *page, struct f2fs_summary *sum,
876			block_t old_blkaddr, block_t new_blkaddr)
877{
878	struct sit_info *sit_i = SIT_I(sbi);
879	struct curseg_info *curseg;
880	unsigned int segno, old_cursegno;
881	struct seg_entry *se;
882	int type;
883
884	segno = GET_SEGNO(sbi, new_blkaddr);
885	se = get_seg_entry(sbi, segno);
886	type = se->type;
887
888	if (se->valid_blocks == 0 && !IS_CURSEG(sbi, segno)) {
889		if (old_blkaddr == NULL_ADDR)
890			type = CURSEG_COLD_DATA;
891		else
892			type = CURSEG_WARM_DATA;
893	}
894	curseg = CURSEG_I(sbi, type);
895
896	mutex_lock(&curseg->curseg_mutex);
897	mutex_lock(&sit_i->sentry_lock);
898
899	old_cursegno = curseg->segno;
900
901	/* change the current segment */
902	if (segno != curseg->segno) {
903		curseg->next_segno = segno;
904		change_curseg(sbi, type, true);
905	}
906
907	curseg->next_blkoff = GET_SEGOFF_FROM_SEG0(sbi, new_blkaddr) &
908					(sbi->blocks_per_seg - 1);
909	__add_sum_entry(sbi, type, sum);
910
911	refresh_sit_entry(sbi, old_blkaddr, new_blkaddr);
912
913	locate_dirty_segment(sbi, old_cursegno);
914	locate_dirty_segment(sbi, GET_SEGNO(sbi, old_blkaddr));
915
916	mutex_unlock(&sit_i->sentry_lock);
917	mutex_unlock(&curseg->curseg_mutex);
918}
919
920void rewrite_node_page(struct f2fs_sb_info *sbi,
921			struct page *page, struct f2fs_summary *sum,
922			block_t old_blkaddr, block_t new_blkaddr)
923{
924	struct sit_info *sit_i = SIT_I(sbi);
925	int type = CURSEG_WARM_NODE;
926	struct curseg_info *curseg;
927	unsigned int segno, old_cursegno;
928	block_t next_blkaddr = next_blkaddr_of_node(page);
929	unsigned int next_segno = GET_SEGNO(sbi, next_blkaddr);
930
931	curseg = CURSEG_I(sbi, type);
932
933	mutex_lock(&curseg->curseg_mutex);
934	mutex_lock(&sit_i->sentry_lock);
935
936	segno = GET_SEGNO(sbi, new_blkaddr);
937	old_cursegno = curseg->segno;
938
939	/* change the current segment */
940	if (segno != curseg->segno) {
941		curseg->next_segno = segno;
942		change_curseg(sbi, type, true);
943	}
944	curseg->next_blkoff = GET_SEGOFF_FROM_SEG0(sbi, new_blkaddr) &
945					(sbi->blocks_per_seg - 1);
946	__add_sum_entry(sbi, type, sum);
947
948	/* change the current log to the next block addr in advance */
949	if (next_segno != segno) {
950		curseg->next_segno = next_segno;
951		change_curseg(sbi, type, true);
952	}
953	curseg->next_blkoff = GET_SEGOFF_FROM_SEG0(sbi, next_blkaddr) &
954					(sbi->blocks_per_seg - 1);
955
956	/* rewrite node page */
957	set_page_writeback(page);
958	submit_write_page(sbi, page, new_blkaddr, NODE);
959	f2fs_submit_bio(sbi, NODE, true);
960	refresh_sit_entry(sbi, old_blkaddr, new_blkaddr);
961
962	locate_dirty_segment(sbi, old_cursegno);
963	locate_dirty_segment(sbi, GET_SEGNO(sbi, old_blkaddr));
964
965	mutex_unlock(&sit_i->sentry_lock);
966	mutex_unlock(&curseg->curseg_mutex);
967}
968
969static int read_compacted_summaries(struct f2fs_sb_info *sbi)
970{
971	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
972	struct curseg_info *seg_i;
973	unsigned char *kaddr;
974	struct page *page;
975	block_t start;
976	int i, j, offset;
977
978	start = start_sum_block(sbi);
979
980	page = get_meta_page(sbi, start++);
981	kaddr = (unsigned char *)page_address(page);
982
983	/* Step 1: restore nat cache */
984	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
985	memcpy(&seg_i->sum_blk->n_nats, kaddr, SUM_JOURNAL_SIZE);
986
987	/* Step 2: restore sit cache */
988	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
989	memcpy(&seg_i->sum_blk->n_sits, kaddr + SUM_JOURNAL_SIZE,
990						SUM_JOURNAL_SIZE);
991	offset = 2 * SUM_JOURNAL_SIZE;
992
993	/* Step 3: restore summary entries */
994	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
995		unsigned short blk_off;
996		unsigned int segno;
997
998		seg_i = CURSEG_I(sbi, i);
999		segno = le32_to_cpu(ckpt->cur_data_segno[i]);
1000		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[i]);
1001		seg_i->next_segno = segno;
1002		reset_curseg(sbi, i, 0);
1003		seg_i->alloc_type = ckpt->alloc_type[i];
1004		seg_i->next_blkoff = blk_off;
1005
1006		if (seg_i->alloc_type == SSR)
1007			blk_off = sbi->blocks_per_seg;
1008
1009		for (j = 0; j < blk_off; j++) {
1010			struct f2fs_summary *s;
1011			s = (struct f2fs_summary *)(kaddr + offset);
1012			seg_i->sum_blk->entries[j] = *s;
1013			offset += SUMMARY_SIZE;
1014			if (offset + SUMMARY_SIZE <= PAGE_CACHE_SIZE -
1015						SUM_FOOTER_SIZE)
1016				continue;
1017
1018			f2fs_put_page(page, 1);
1019			page = NULL;
1020
1021			page = get_meta_page(sbi, start++);
1022			kaddr = (unsigned char *)page_address(page);
1023			offset = 0;
1024		}
1025	}
1026	f2fs_put_page(page, 1);
1027	return 0;
1028}
1029
1030static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
1031{
1032	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1033	struct f2fs_summary_block *sum;
1034	struct curseg_info *curseg;
1035	struct page *new;
1036	unsigned short blk_off;
1037	unsigned int segno = 0;
1038	block_t blk_addr = 0;
1039
1040	/* get segment number and block addr */
1041	if (IS_DATASEG(type)) {
1042		segno = le32_to_cpu(ckpt->cur_data_segno[type]);
1043		blk_off = le16_to_cpu(ckpt->cur_data_blkoff[type -
1044							CURSEG_HOT_DATA]);
1045		if (is_set_ckpt_flags(ckpt, CP_UMOUNT_FLAG))
1046			blk_addr = sum_blk_addr(sbi, NR_CURSEG_TYPE, type);
1047		else
1048			blk_addr = sum_blk_addr(sbi, NR_CURSEG_DATA_TYPE, type);
1049	} else {
1050		segno = le32_to_cpu(ckpt->cur_node_segno[type -
1051							CURSEG_HOT_NODE]);
1052		blk_off = le16_to_cpu(ckpt->cur_node_blkoff[type -
1053							CURSEG_HOT_NODE]);
1054		if (is_set_ckpt_flags(ckpt, CP_UMOUNT_FLAG))
1055			blk_addr = sum_blk_addr(sbi, NR_CURSEG_NODE_TYPE,
1056							type - CURSEG_HOT_NODE);
1057		else
1058			blk_addr = GET_SUM_BLOCK(sbi, segno);
1059	}
1060
1061	new = get_meta_page(sbi, blk_addr);
1062	sum = (struct f2fs_summary_block *)page_address(new);
1063
1064	if (IS_NODESEG(type)) {
1065		if (is_set_ckpt_flags(ckpt, CP_UMOUNT_FLAG)) {
1066			struct f2fs_summary *ns = &sum->entries[0];
1067			int i;
1068			for (i = 0; i < sbi->blocks_per_seg; i++, ns++) {
1069				ns->version = 0;
1070				ns->ofs_in_node = 0;
1071			}
1072		} else {
1073			if (restore_node_summary(sbi, segno, sum)) {
1074				f2fs_put_page(new, 1);
1075				return -EINVAL;
1076			}
1077		}
1078	}
1079
1080	/* set uncompleted segment to curseg */
1081	curseg = CURSEG_I(sbi, type);
1082	mutex_lock(&curseg->curseg_mutex);
1083	memcpy(curseg->sum_blk, sum, PAGE_CACHE_SIZE);
1084	curseg->next_segno = segno;
1085	reset_curseg(sbi, type, 0);
1086	curseg->alloc_type = ckpt->alloc_type[type];
1087	curseg->next_blkoff = blk_off;
1088	mutex_unlock(&curseg->curseg_mutex);
1089	f2fs_put_page(new, 1);
1090	return 0;
1091}
1092
1093static int restore_curseg_summaries(struct f2fs_sb_info *sbi)
1094{
1095	int type = CURSEG_HOT_DATA;
1096
1097	if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_COMPACT_SUM_FLAG)) {
1098		/* restore for compacted data summary */
1099		if (read_compacted_summaries(sbi))
1100			return -EINVAL;
1101		type = CURSEG_HOT_NODE;
1102	}
1103
1104	for (; type <= CURSEG_COLD_NODE; type++)
1105		if (read_normal_summaries(sbi, type))
1106			return -EINVAL;
1107	return 0;
1108}
1109
1110static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr)
1111{
1112	struct page *page;
1113	unsigned char *kaddr;
1114	struct f2fs_summary *summary;
1115	struct curseg_info *seg_i;
1116	int written_size = 0;
1117	int i, j;
1118
1119	page = grab_meta_page(sbi, blkaddr++);
1120	kaddr = (unsigned char *)page_address(page);
1121
1122	/* Step 1: write nat cache */
1123	seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
1124	memcpy(kaddr, &seg_i->sum_blk->n_nats, SUM_JOURNAL_SIZE);
1125	written_size += SUM_JOURNAL_SIZE;
1126
1127	/* Step 2: write sit cache */
1128	seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
1129	memcpy(kaddr + written_size, &seg_i->sum_blk->n_sits,
1130						SUM_JOURNAL_SIZE);
1131	written_size += SUM_JOURNAL_SIZE;
1132
1133	set_page_dirty(page);
1134
1135	/* Step 3: write summary entries */
1136	for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1137		unsigned short blkoff;
1138		seg_i = CURSEG_I(sbi, i);
1139		if (sbi->ckpt->alloc_type[i] == SSR)
1140			blkoff = sbi->blocks_per_seg;
1141		else
1142			blkoff = curseg_blkoff(sbi, i);
1143
1144		for (j = 0; j < blkoff; j++) {
1145			if (!page) {
1146				page = grab_meta_page(sbi, blkaddr++);
1147				kaddr = (unsigned char *)page_address(page);
1148				written_size = 0;
1149			}
1150			summary = (struct f2fs_summary *)(kaddr + written_size);
1151			*summary = seg_i->sum_blk->entries[j];
1152			written_size += SUMMARY_SIZE;
1153			set_page_dirty(page);
1154
1155			if (written_size + SUMMARY_SIZE <= PAGE_CACHE_SIZE -
1156							SUM_FOOTER_SIZE)
1157				continue;
1158
1159			f2fs_put_page(page, 1);
1160			page = NULL;
1161		}
1162	}
1163	if (page)
1164		f2fs_put_page(page, 1);
1165}
1166
1167static void write_normal_summaries(struct f2fs_sb_info *sbi,
1168					block_t blkaddr, int type)
1169{
1170	int i, end;
1171	if (IS_DATASEG(type))
1172		end = type + NR_CURSEG_DATA_TYPE;
1173	else
1174		end = type + NR_CURSEG_NODE_TYPE;
1175
1176	for (i = type; i < end; i++) {
1177		struct curseg_info *sum = CURSEG_I(sbi, i);
1178		mutex_lock(&sum->curseg_mutex);
1179		write_sum_page(sbi, sum->sum_blk, blkaddr + (i - type));
1180		mutex_unlock(&sum->curseg_mutex);
1181	}
1182}
1183
1184void write_data_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
1185{
1186	if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_COMPACT_SUM_FLAG))
1187		write_compacted_summaries(sbi, start_blk);
1188	else
1189		write_normal_summaries(sbi, start_blk, CURSEG_HOT_DATA);
1190}
1191
1192void write_node_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
1193{
1194	if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_UMOUNT_FLAG))
1195		write_normal_summaries(sbi, start_blk, CURSEG_HOT_NODE);
1196}
1197
1198int lookup_journal_in_cursum(struct f2fs_summary_block *sum, int type,
1199					unsigned int val, int alloc)
1200{
1201	int i;
1202
1203	if (type == NAT_JOURNAL) {
1204		for (i = 0; i < nats_in_cursum(sum); i++) {
1205			if (le32_to_cpu(nid_in_journal(sum, i)) == val)
1206				return i;
1207		}
1208		if (alloc && nats_in_cursum(sum) < NAT_JOURNAL_ENTRIES)
1209			return update_nats_in_cursum(sum, 1);
1210	} else if (type == SIT_JOURNAL) {
1211		for (i = 0; i < sits_in_cursum(sum); i++)
1212			if (le32_to_cpu(segno_in_journal(sum, i)) == val)
1213				return i;
1214		if (alloc && sits_in_cursum(sum) < SIT_JOURNAL_ENTRIES)
1215			return update_sits_in_cursum(sum, 1);
1216	}
1217	return -1;
1218}
1219
1220static struct page *get_current_sit_page(struct f2fs_sb_info *sbi,
1221					unsigned int segno)
1222{
1223	struct sit_info *sit_i = SIT_I(sbi);
1224	unsigned int offset = SIT_BLOCK_OFFSET(sit_i, segno);
1225	block_t blk_addr = sit_i->sit_base_addr + offset;
1226
1227	check_seg_range(sbi, segno);
1228
1229	/* calculate sit block address */
1230	if (f2fs_test_bit(offset, sit_i->sit_bitmap))
1231		blk_addr += sit_i->sit_blocks;
1232
1233	return get_meta_page(sbi, blk_addr);
1234}
1235
1236static struct page *get_next_sit_page(struct f2fs_sb_info *sbi,
1237					unsigned int start)
1238{
1239	struct sit_info *sit_i = SIT_I(sbi);
1240	struct page *src_page, *dst_page;
1241	pgoff_t src_off, dst_off;
1242	void *src_addr, *dst_addr;
1243
1244	src_off = current_sit_addr(sbi, start);
1245	dst_off = next_sit_addr(sbi, src_off);
1246
1247	/* get current sit block page without lock */
1248	src_page = get_meta_page(sbi, src_off);
1249	dst_page = grab_meta_page(sbi, dst_off);
1250	BUG_ON(PageDirty(src_page));
1251
1252	src_addr = page_address(src_page);
1253	dst_addr = page_address(dst_page);
1254	memcpy(dst_addr, src_addr, PAGE_CACHE_SIZE);
1255
1256	set_page_dirty(dst_page);
1257	f2fs_put_page(src_page, 1);
1258
1259	set_to_next_sit(sit_i, start);
1260
1261	return dst_page;
1262}
1263
1264static bool flush_sits_in_journal(struct f2fs_sb_info *sbi)
1265{
1266	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
1267	struct f2fs_summary_block *sum = curseg->sum_blk;
1268	int i;
1269
1270	/*
1271	 * If the journal area in the current summary is full of sit entries,
1272	 * all the sit entries will be flushed. Otherwise the sit entries
1273	 * are not able to replace with newly hot sit entries.
1274	 */
1275	if (sits_in_cursum(sum) >= SIT_JOURNAL_ENTRIES) {
1276		for (i = sits_in_cursum(sum) - 1; i >= 0; i--) {
1277			unsigned int segno;
1278			segno = le32_to_cpu(segno_in_journal(sum, i));
1279			__mark_sit_entry_dirty(sbi, segno);
1280		}
1281		update_sits_in_cursum(sum, -sits_in_cursum(sum));
1282		return true;
1283	}
1284	return false;
1285}
1286
1287/*
1288 * CP calls this function, which flushes SIT entries including sit_journal,
1289 * and moves prefree segs to free segs.
1290 */
1291void flush_sit_entries(struct f2fs_sb_info *sbi)
1292{
1293	struct sit_info *sit_i = SIT_I(sbi);
1294	unsigned long *bitmap = sit_i->dirty_sentries_bitmap;
1295	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
1296	struct f2fs_summary_block *sum = curseg->sum_blk;
1297	unsigned long nsegs = TOTAL_SEGS(sbi);
1298	struct page *page = NULL;
1299	struct f2fs_sit_block *raw_sit = NULL;
1300	unsigned int start = 0, end = 0;
1301	unsigned int segno = -1;
1302	bool flushed;
1303
1304	mutex_lock(&curseg->curseg_mutex);
1305	mutex_lock(&sit_i->sentry_lock);
1306
1307	/*
1308	 * "flushed" indicates whether sit entries in journal are flushed
1309	 * to the SIT area or not.
1310	 */
1311	flushed = flush_sits_in_journal(sbi);
1312
1313	while ((segno = find_next_bit(bitmap, nsegs, segno + 1)) < nsegs) {
1314		struct seg_entry *se = get_seg_entry(sbi, segno);
1315		int sit_offset, offset;
1316
1317		sit_offset = SIT_ENTRY_OFFSET(sit_i, segno);
1318
1319		if (flushed)
1320			goto to_sit_page;
1321
1322		offset = lookup_journal_in_cursum(sum, SIT_JOURNAL, segno, 1);
1323		if (offset >= 0) {
1324			segno_in_journal(sum, offset) = cpu_to_le32(segno);
1325			seg_info_to_raw_sit(se, &sit_in_journal(sum, offset));
1326			goto flush_done;
1327		}
1328to_sit_page:
1329		if (!page || (start > segno) || (segno > end)) {
1330			if (page) {
1331				f2fs_put_page(page, 1);
1332				page = NULL;
1333			}
1334
1335			start = START_SEGNO(sit_i, segno);
1336			end = start + SIT_ENTRY_PER_BLOCK - 1;
1337
1338			/* read sit block that will be updated */
1339			page = get_next_sit_page(sbi, start);
1340			raw_sit = page_address(page);
1341		}
1342
1343		/* udpate entry in SIT block */
1344		seg_info_to_raw_sit(se, &raw_sit->entries[sit_offset]);
1345flush_done:
1346		__clear_bit(segno, bitmap);
1347		sit_i->dirty_sentries--;
1348	}
1349	mutex_unlock(&sit_i->sentry_lock);
1350	mutex_unlock(&curseg->curseg_mutex);
1351
1352	/* writeout last modified SIT block */
1353	f2fs_put_page(page, 1);
1354
1355	set_prefree_as_free_segments(sbi);
1356}
1357
1358static int build_sit_info(struct f2fs_sb_info *sbi)
1359{
1360	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
1361	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1362	struct sit_info *sit_i;
1363	unsigned int sit_segs, start;
1364	char *src_bitmap, *dst_bitmap;
1365	unsigned int bitmap_size;
1366
1367	/* allocate memory for SIT information */
1368	sit_i = kzalloc(sizeof(struct sit_info), GFP_KERNEL);
1369	if (!sit_i)
1370		return -ENOMEM;
1371
1372	SM_I(sbi)->sit_info = sit_i;
1373
1374	sit_i->sentries = vzalloc(TOTAL_SEGS(sbi) * sizeof(struct seg_entry));
1375	if (!sit_i->sentries)
1376		return -ENOMEM;
1377
1378	bitmap_size = f2fs_bitmap_size(TOTAL_SEGS(sbi));
1379	sit_i->dirty_sentries_bitmap = kzalloc(bitmap_size, GFP_KERNEL);
1380	if (!sit_i->dirty_sentries_bitmap)
1381		return -ENOMEM;
1382
1383	for (start = 0; start < TOTAL_SEGS(sbi); start++) {
1384		sit_i->sentries[start].cur_valid_map
1385			= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
1386		sit_i->sentries[start].ckpt_valid_map
1387			= kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
1388		if (!sit_i->sentries[start].cur_valid_map
1389				|| !sit_i->sentries[start].ckpt_valid_map)
1390			return -ENOMEM;
1391	}
1392
1393	if (sbi->segs_per_sec > 1) {
1394		sit_i->sec_entries = vzalloc(TOTAL_SECS(sbi) *
1395					sizeof(struct sec_entry));
1396		if (!sit_i->sec_entries)
1397			return -ENOMEM;
1398	}
1399
1400	/* get information related with SIT */
1401	sit_segs = le32_to_cpu(raw_super->segment_count_sit) >> 1;
1402
1403	/* setup SIT bitmap from ckeckpoint pack */
1404	bitmap_size = __bitmap_size(sbi, SIT_BITMAP);
1405	src_bitmap = __bitmap_ptr(sbi, SIT_BITMAP);
1406
1407	dst_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
1408	if (!dst_bitmap)
1409		return -ENOMEM;
1410
1411	/* init SIT information */
1412	sit_i->s_ops = &default_salloc_ops;
1413
1414	sit_i->sit_base_addr = le32_to_cpu(raw_super->sit_blkaddr);
1415	sit_i->sit_blocks = sit_segs << sbi->log_blocks_per_seg;
1416	sit_i->written_valid_blocks = le64_to_cpu(ckpt->valid_block_count);
1417	sit_i->sit_bitmap = dst_bitmap;
1418	sit_i->bitmap_size = bitmap_size;
1419	sit_i->dirty_sentries = 0;
1420	sit_i->sents_per_block = SIT_ENTRY_PER_BLOCK;
1421	sit_i->elapsed_time = le64_to_cpu(sbi->ckpt->elapsed_time);
1422	sit_i->mounted_time = CURRENT_TIME_SEC.tv_sec;
1423	mutex_init(&sit_i->sentry_lock);
1424	return 0;
1425}
1426
1427static int build_free_segmap(struct f2fs_sb_info *sbi)
1428{
1429	struct f2fs_sm_info *sm_info = SM_I(sbi);
1430	struct free_segmap_info *free_i;
1431	unsigned int bitmap_size, sec_bitmap_size;
1432
1433	/* allocate memory for free segmap information */
1434	free_i = kzalloc(sizeof(struct free_segmap_info), GFP_KERNEL);
1435	if (!free_i)
1436		return -ENOMEM;
1437
1438	SM_I(sbi)->free_info = free_i;
1439
1440	bitmap_size = f2fs_bitmap_size(TOTAL_SEGS(sbi));
1441	free_i->free_segmap = kmalloc(bitmap_size, GFP_KERNEL);
1442	if (!free_i->free_segmap)
1443		return -ENOMEM;
1444
1445	sec_bitmap_size = f2fs_bitmap_size(TOTAL_SECS(sbi));
1446	free_i->free_secmap = kmalloc(sec_bitmap_size, GFP_KERNEL);
1447	if (!free_i->free_secmap)
1448		return -ENOMEM;
1449
1450	/* set all segments as dirty temporarily */
1451	memset(free_i->free_segmap, 0xff, bitmap_size);
1452	memset(free_i->free_secmap, 0xff, sec_bitmap_size);
1453
1454	/* init free segmap information */
1455	free_i->start_segno =
1456		(unsigned int) GET_SEGNO_FROM_SEG0(sbi, sm_info->main_blkaddr);
1457	free_i->free_segments = 0;
1458	free_i->free_sections = 0;
1459	rwlock_init(&free_i->segmap_lock);
1460	return 0;
1461}
1462
1463static int build_curseg(struct f2fs_sb_info *sbi)
1464{
1465	struct curseg_info *array;
1466	int i;
1467
1468	array = kzalloc(sizeof(*array) * NR_CURSEG_TYPE, GFP_KERNEL);
1469	if (!array)
1470		return -ENOMEM;
1471
1472	SM_I(sbi)->curseg_array = array;
1473
1474	for (i = 0; i < NR_CURSEG_TYPE; i++) {
1475		mutex_init(&array[i].curseg_mutex);
1476		array[i].sum_blk = kzalloc(PAGE_CACHE_SIZE, GFP_KERNEL);
1477		if (!array[i].sum_blk)
1478			return -ENOMEM;
1479		array[i].segno = NULL_SEGNO;
1480		array[i].next_blkoff = 0;
1481	}
1482	return restore_curseg_summaries(sbi);
1483}
1484
1485static void build_sit_entries(struct f2fs_sb_info *sbi)
1486{
1487	struct sit_info *sit_i = SIT_I(sbi);
1488	struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
1489	struct f2fs_summary_block *sum = curseg->sum_blk;
1490	unsigned int start;
1491
1492	for (start = 0; start < TOTAL_SEGS(sbi); start++) {
1493		struct seg_entry *se = &sit_i->sentries[start];
1494		struct f2fs_sit_block *sit_blk;
1495		struct f2fs_sit_entry sit;
1496		struct page *page;
1497		int i;
1498
1499		mutex_lock(&curseg->curseg_mutex);
1500		for (i = 0; i < sits_in_cursum(sum); i++) {
1501			if (le32_to_cpu(segno_in_journal(sum, i)) == start) {
1502				sit = sit_in_journal(sum, i);
1503				mutex_unlock(&curseg->curseg_mutex);
1504				goto got_it;
1505			}
1506		}
1507		mutex_unlock(&curseg->curseg_mutex);
1508		page = get_current_sit_page(sbi, start);
1509		sit_blk = (struct f2fs_sit_block *)page_address(page);
1510		sit = sit_blk->entries[SIT_ENTRY_OFFSET(sit_i, start)];
1511		f2fs_put_page(page, 1);
1512got_it:
1513		check_block_count(sbi, start, &sit);
1514		seg_info_from_raw_sit(se, &sit);
1515		if (sbi->segs_per_sec > 1) {
1516			struct sec_entry *e = get_sec_entry(sbi, start);
1517			e->valid_blocks += se->valid_blocks;
1518		}
1519	}
1520}
1521
1522static void init_free_segmap(struct f2fs_sb_info *sbi)
1523{
1524	unsigned int start;
1525	int type;
1526
1527	for (start = 0; start < TOTAL_SEGS(sbi); start++) {
1528		struct seg_entry *sentry = get_seg_entry(sbi, start);
1529		if (!sentry->valid_blocks)
1530			__set_free(sbi, start);
1531	}
1532
1533	/* set use the current segments */
1534	for (type = CURSEG_HOT_DATA; type <= CURSEG_COLD_NODE; type++) {
1535		struct curseg_info *curseg_t = CURSEG_I(sbi, type);
1536		__set_test_and_inuse(sbi, curseg_t->segno);
1537	}
1538}
1539
1540static void init_dirty_segmap(struct f2fs_sb_info *sbi)
1541{
1542	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1543	struct free_segmap_info *free_i = FREE_I(sbi);
1544	unsigned int segno = 0, offset = 0, total_segs = TOTAL_SEGS(sbi);
1545	unsigned short valid_blocks;
1546
1547	while (1) {
1548		/* find dirty segment based on free segmap */
1549		segno = find_next_inuse(free_i, total_segs, offset);
1550		if (segno >= total_segs)
1551			break;
1552		offset = segno + 1;
1553		valid_blocks = get_valid_blocks(sbi, segno, 0);
1554		if (valid_blocks >= sbi->blocks_per_seg || !valid_blocks)
1555			continue;
1556		mutex_lock(&dirty_i->seglist_lock);
1557		__locate_dirty_segment(sbi, segno, DIRTY);
1558		mutex_unlock(&dirty_i->seglist_lock);
1559	}
1560}
1561
1562static int init_victim_secmap(struct f2fs_sb_info *sbi)
1563{
1564	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1565	unsigned int bitmap_size = f2fs_bitmap_size(TOTAL_SECS(sbi));
1566
1567	dirty_i->victim_secmap = kzalloc(bitmap_size, GFP_KERNEL);
1568	if (!dirty_i->victim_secmap)
1569		return -ENOMEM;
1570	return 0;
1571}
1572
1573static int build_dirty_segmap(struct f2fs_sb_info *sbi)
1574{
1575	struct dirty_seglist_info *dirty_i;
1576	unsigned int bitmap_size, i;
1577
1578	/* allocate memory for dirty segments list information */
1579	dirty_i = kzalloc(sizeof(struct dirty_seglist_info), GFP_KERNEL);
1580	if (!dirty_i)
1581		return -ENOMEM;
1582
1583	SM_I(sbi)->dirty_info = dirty_i;
1584	mutex_init(&dirty_i->seglist_lock);
1585
1586	bitmap_size = f2fs_bitmap_size(TOTAL_SEGS(sbi));
1587
1588	for (i = 0; i < NR_DIRTY_TYPE; i++) {
1589		dirty_i->dirty_segmap[i] = kzalloc(bitmap_size, GFP_KERNEL);
1590		if (!dirty_i->dirty_segmap[i])
1591			return -ENOMEM;
1592	}
1593
1594	init_dirty_segmap(sbi);
1595	return init_victim_secmap(sbi);
1596}
1597
1598/*
1599 * Update min, max modified time for cost-benefit GC algorithm
1600 */
1601static void init_min_max_mtime(struct f2fs_sb_info *sbi)
1602{
1603	struct sit_info *sit_i = SIT_I(sbi);
1604	unsigned int segno;
1605
1606	mutex_lock(&sit_i->sentry_lock);
1607
1608	sit_i->min_mtime = LLONG_MAX;
1609
1610	for (segno = 0; segno < TOTAL_SEGS(sbi); segno += sbi->segs_per_sec) {
1611		unsigned int i;
1612		unsigned long long mtime = 0;
1613
1614		for (i = 0; i < sbi->segs_per_sec; i++)
1615			mtime += get_seg_entry(sbi, segno + i)->mtime;
1616
1617		mtime = div_u64(mtime, sbi->segs_per_sec);
1618
1619		if (sit_i->min_mtime > mtime)
1620			sit_i->min_mtime = mtime;
1621	}
1622	sit_i->max_mtime = get_mtime(sbi);
1623	mutex_unlock(&sit_i->sentry_lock);
1624}
1625
1626int build_segment_manager(struct f2fs_sb_info *sbi)
1627{
1628	struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
1629	struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1630	struct f2fs_sm_info *sm_info;
1631	int err;
1632
1633	sm_info = kzalloc(sizeof(struct f2fs_sm_info), GFP_KERNEL);
1634	if (!sm_info)
1635		return -ENOMEM;
1636
1637	/* init sm info */
1638	sbi->sm_info = sm_info;
1639	INIT_LIST_HEAD(&sm_info->wblist_head);
1640	spin_lock_init(&sm_info->wblist_lock);
1641	sm_info->seg0_blkaddr = le32_to_cpu(raw_super->segment0_blkaddr);
1642	sm_info->main_blkaddr = le32_to_cpu(raw_super->main_blkaddr);
1643	sm_info->segment_count = le32_to_cpu(raw_super->segment_count);
1644	sm_info->reserved_segments = le32_to_cpu(ckpt->rsvd_segment_count);
1645	sm_info->ovp_segments = le32_to_cpu(ckpt->overprov_segment_count);
1646	sm_info->main_segments = le32_to_cpu(raw_super->segment_count_main);
1647	sm_info->ssa_blkaddr = le32_to_cpu(raw_super->ssa_blkaddr);
1648
1649	err = build_sit_info(sbi);
1650	if (err)
1651		return err;
1652	err = build_free_segmap(sbi);
1653	if (err)
1654		return err;
1655	err = build_curseg(sbi);
1656	if (err)
1657		return err;
1658
1659	/* reinit free segmap based on SIT */
1660	build_sit_entries(sbi);
1661
1662	init_free_segmap(sbi);
1663	err = build_dirty_segmap(sbi);
1664	if (err)
1665		return err;
1666
1667	init_min_max_mtime(sbi);
1668	return 0;
1669}
1670
1671static void discard_dirty_segmap(struct f2fs_sb_info *sbi,
1672		enum dirty_type dirty_type)
1673{
1674	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1675
1676	mutex_lock(&dirty_i->seglist_lock);
1677	kfree(dirty_i->dirty_segmap[dirty_type]);
1678	dirty_i->nr_dirty[dirty_type] = 0;
1679	mutex_unlock(&dirty_i->seglist_lock);
1680}
1681
1682static void destroy_victim_secmap(struct f2fs_sb_info *sbi)
1683{
1684	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1685	kfree(dirty_i->victim_secmap);
1686}
1687
1688static void destroy_dirty_segmap(struct f2fs_sb_info *sbi)
1689{
1690	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1691	int i;
1692
1693	if (!dirty_i)
1694		return;
1695
1696	/* discard pre-free/dirty segments list */
1697	for (i = 0; i < NR_DIRTY_TYPE; i++)
1698		discard_dirty_segmap(sbi, i);
1699
1700	destroy_victim_secmap(sbi);
1701	SM_I(sbi)->dirty_info = NULL;
1702	kfree(dirty_i);
1703}
1704
1705static void destroy_curseg(struct f2fs_sb_info *sbi)
1706{
1707	struct curseg_info *array = SM_I(sbi)->curseg_array;
1708	int i;
1709
1710	if (!array)
1711		return;
1712	SM_I(sbi)->curseg_array = NULL;
1713	for (i = 0; i < NR_CURSEG_TYPE; i++)
1714		kfree(array[i].sum_blk);
1715	kfree(array);
1716}
1717
1718static void destroy_free_segmap(struct f2fs_sb_info *sbi)
1719{
1720	struct free_segmap_info *free_i = SM_I(sbi)->free_info;
1721	if (!free_i)
1722		return;
1723	SM_I(sbi)->free_info = NULL;
1724	kfree(free_i->free_segmap);
1725	kfree(free_i->free_secmap);
1726	kfree(free_i);
1727}
1728
1729static void destroy_sit_info(struct f2fs_sb_info *sbi)
1730{
1731	struct sit_info *sit_i = SIT_I(sbi);
1732	unsigned int start;
1733
1734	if (!sit_i)
1735		return;
1736
1737	if (sit_i->sentries) {
1738		for (start = 0; start < TOTAL_SEGS(sbi); start++) {
1739			kfree(sit_i->sentries[start].cur_valid_map);
1740			kfree(sit_i->sentries[start].ckpt_valid_map);
1741		}
1742	}
1743	vfree(sit_i->sentries);
1744	vfree(sit_i->sec_entries);
1745	kfree(sit_i->dirty_sentries_bitmap);
1746
1747	SM_I(sbi)->sit_info = NULL;
1748	kfree(sit_i->sit_bitmap);
1749	kfree(sit_i);
1750}
1751
1752void destroy_segment_manager(struct f2fs_sb_info *sbi)
1753{
1754	struct f2fs_sm_info *sm_info = SM_I(sbi);
1755	destroy_dirty_segmap(sbi);
1756	destroy_curseg(sbi);
1757	destroy_free_segmap(sbi);
1758	destroy_sit_info(sbi);
1759	sbi->sm_info = NULL;
1760	kfree(sm_info);
1761}
1762