f2fs: avoid returning uninitialized value to userspace from f2fs_trim_fs()
[firefly-linux-kernel-4.4.55.git] / fs / f2fs / segment.c
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/kthread.h>
17 #include <linux/vmalloc.h>
18 #include <linux/swap.h>
19
20 #include "f2fs.h"
21 #include "segment.h"
22 #include "node.h"
23 #include <trace/events/f2fs.h>
24
25 #define __reverse_ffz(x) __reverse_ffs(~(x))
26
27 static struct kmem_cache *discard_entry_slab;
28 static struct kmem_cache *sit_entry_set_slab;
29 static struct kmem_cache *inmem_entry_slab;
30
31 /*
32  * __reverse_ffs is copied from include/asm-generic/bitops/__ffs.h since
33  * MSB and LSB are reversed in a byte by f2fs_set_bit.
34  */
35 static inline unsigned long __reverse_ffs(unsigned long word)
36 {
37         int num = 0;
38
39 #if BITS_PER_LONG == 64
40         if ((word & 0xffffffff) == 0) {
41                 num += 32;
42                 word >>= 32;
43         }
44 #endif
45         if ((word & 0xffff) == 0) {
46                 num += 16;
47                 word >>= 16;
48         }
49         if ((word & 0xff) == 0) {
50                 num += 8;
51                 word >>= 8;
52         }
53         if ((word & 0xf0) == 0)
54                 num += 4;
55         else
56                 word >>= 4;
57         if ((word & 0xc) == 0)
58                 num += 2;
59         else
60                 word >>= 2;
61         if ((word & 0x2) == 0)
62                 num += 1;
63         return num;
64 }
65
66 /*
67  * __find_rev_next(_zero)_bit is copied from lib/find_next_bit.c because
68  * f2fs_set_bit makes MSB and LSB reversed in a byte.
69  * Example:
70  *                             LSB <--> MSB
71  *   f2fs_set_bit(0, bitmap) => 0000 0001
72  *   f2fs_set_bit(7, bitmap) => 1000 0000
73  */
74 static unsigned long __find_rev_next_bit(const unsigned long *addr,
75                         unsigned long size, unsigned long offset)
76 {
77         const unsigned long *p = addr + BIT_WORD(offset);
78         unsigned long result = offset & ~(BITS_PER_LONG - 1);
79         unsigned long tmp;
80         unsigned long mask, submask;
81         unsigned long quot, rest;
82
83         if (offset >= size)
84                 return size;
85
86         size -= result;
87         offset %= BITS_PER_LONG;
88         if (!offset)
89                 goto aligned;
90
91         tmp = *(p++);
92         quot = (offset >> 3) << 3;
93         rest = offset & 0x7;
94         mask = ~0UL << quot;
95         submask = (unsigned char)(0xff << rest) >> rest;
96         submask <<= quot;
97         mask &= submask;
98         tmp &= mask;
99         if (size < BITS_PER_LONG)
100                 goto found_first;
101         if (tmp)
102                 goto found_middle;
103
104         size -= BITS_PER_LONG;
105         result += BITS_PER_LONG;
106 aligned:
107         while (size & ~(BITS_PER_LONG-1)) {
108                 tmp = *(p++);
109                 if (tmp)
110                         goto found_middle;
111                 result += BITS_PER_LONG;
112                 size -= BITS_PER_LONG;
113         }
114         if (!size)
115                 return result;
116         tmp = *p;
117 found_first:
118         tmp &= (~0UL >> (BITS_PER_LONG - size));
119         if (tmp == 0UL)         /* Are any bits set? */
120                 return result + size;   /* Nope. */
121 found_middle:
122         return result + __reverse_ffs(tmp);
123 }
124
125 static unsigned long __find_rev_next_zero_bit(const unsigned long *addr,
126                         unsigned long size, unsigned long offset)
127 {
128         const unsigned long *p = addr + BIT_WORD(offset);
129         unsigned long result = offset & ~(BITS_PER_LONG - 1);
130         unsigned long tmp;
131         unsigned long mask, submask;
132         unsigned long quot, rest;
133
134         if (offset >= size)
135                 return size;
136
137         size -= result;
138         offset %= BITS_PER_LONG;
139         if (!offset)
140                 goto aligned;
141
142         tmp = *(p++);
143         quot = (offset >> 3) << 3;
144         rest = offset & 0x7;
145         mask = ~(~0UL << quot);
146         submask = (unsigned char)~((unsigned char)(0xff << rest) >> rest);
147         submask <<= quot;
148         mask += submask;
149         tmp |= mask;
150         if (size < BITS_PER_LONG)
151                 goto found_first;
152         if (~tmp)
153                 goto found_middle;
154
155         size -= BITS_PER_LONG;
156         result += BITS_PER_LONG;
157 aligned:
158         while (size & ~(BITS_PER_LONG - 1)) {
159                 tmp = *(p++);
160                 if (~tmp)
161                         goto found_middle;
162                 result += BITS_PER_LONG;
163                 size -= BITS_PER_LONG;
164         }
165         if (!size)
166                 return result;
167         tmp = *p;
168
169 found_first:
170         tmp |= ~0UL << size;
171         if (tmp == ~0UL)        /* Are any bits zero? */
172                 return result + size;   /* Nope. */
173 found_middle:
174         return result + __reverse_ffz(tmp);
175 }
176
177 void register_inmem_page(struct inode *inode, struct page *page)
178 {
179         struct f2fs_inode_info *fi = F2FS_I(inode);
180         struct inmem_pages *new;
181         int err;
182 retry:
183         new = f2fs_kmem_cache_alloc(inmem_entry_slab, GFP_NOFS);
184
185         /* add atomic page indices to the list */
186         new->page = page;
187         INIT_LIST_HEAD(&new->list);
188
189         /* increase reference count with clean state */
190         mutex_lock(&fi->inmem_lock);
191         err = radix_tree_insert(&fi->inmem_root, page->index, new);
192         if (err == -EEXIST) {
193                 mutex_unlock(&fi->inmem_lock);
194                 kmem_cache_free(inmem_entry_slab, new);
195                 return;
196         } else if (err) {
197                 mutex_unlock(&fi->inmem_lock);
198                 kmem_cache_free(inmem_entry_slab, new);
199                 goto retry;
200         }
201         get_page(page);
202         list_add_tail(&new->list, &fi->inmem_pages);
203         mutex_unlock(&fi->inmem_lock);
204 }
205
206 void invalidate_inmem_page(struct inode *inode, struct page *page)
207 {
208         struct f2fs_inode_info *fi = F2FS_I(inode);
209         struct inmem_pages *cur;
210
211         mutex_lock(&fi->inmem_lock);
212         cur = radix_tree_lookup(&fi->inmem_root, page->index);
213         if (cur) {
214                 radix_tree_delete(&fi->inmem_root, cur->page->index);
215                 f2fs_put_page(cur->page, 0);
216                 list_del(&cur->list);
217                 kmem_cache_free(inmem_entry_slab, cur);
218         }
219         mutex_unlock(&fi->inmem_lock);
220 }
221
222 void commit_inmem_pages(struct inode *inode, bool abort)
223 {
224         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
225         struct f2fs_inode_info *fi = F2FS_I(inode);
226         struct inmem_pages *cur, *tmp;
227         bool submit_bio = false;
228         struct f2fs_io_info fio = {
229                 .type = DATA,
230                 .rw = WRITE_SYNC,
231         };
232
233         f2fs_balance_fs(sbi);
234         f2fs_lock_op(sbi);
235
236         mutex_lock(&fi->inmem_lock);
237         list_for_each_entry_safe(cur, tmp, &fi->inmem_pages, list) {
238                 lock_page(cur->page);
239                 if (!abort && cur->page->mapping == inode->i_mapping) {
240                         f2fs_wait_on_page_writeback(cur->page, DATA);
241                         if (clear_page_dirty_for_io(cur->page))
242                                 inode_dec_dirty_pages(inode);
243                         do_write_data_page(cur->page, &fio);
244                         submit_bio = true;
245                 }
246                 radix_tree_delete(&fi->inmem_root, cur->page->index);
247                 f2fs_put_page(cur->page, 1);
248                 list_del(&cur->list);
249                 kmem_cache_free(inmem_entry_slab, cur);
250         }
251         if (submit_bio)
252                 f2fs_submit_merged_bio(sbi, DATA, WRITE);
253         mutex_unlock(&fi->inmem_lock);
254
255         filemap_fdatawait_range(inode->i_mapping, 0, LLONG_MAX);
256         f2fs_unlock_op(sbi);
257 }
258
259 /*
260  * This function balances dirty node and dentry pages.
261  * In addition, it controls garbage collection.
262  */
263 void f2fs_balance_fs(struct f2fs_sb_info *sbi)
264 {
265         /*
266          * We should do GC or end up with checkpoint, if there are so many dirty
267          * dir/node pages without enough free segments.
268          */
269         if (has_not_enough_free_secs(sbi, 0)) {
270                 mutex_lock(&sbi->gc_mutex);
271                 f2fs_gc(sbi);
272         }
273 }
274
275 void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi)
276 {
277         /* check the # of cached NAT entries and prefree segments */
278         if (try_to_free_nats(sbi, NAT_ENTRY_PER_BLOCK) ||
279                                 excess_prefree_segs(sbi))
280                 f2fs_sync_fs(sbi->sb, true);
281 }
282
283 static int issue_flush_thread(void *data)
284 {
285         struct f2fs_sb_info *sbi = data;
286         struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
287         wait_queue_head_t *q = &fcc->flush_wait_queue;
288 repeat:
289         if (kthread_should_stop())
290                 return 0;
291
292         if (!llist_empty(&fcc->issue_list)) {
293                 struct bio *bio = bio_alloc(GFP_NOIO, 0);
294                 struct flush_cmd *cmd, *next;
295                 int ret;
296
297                 fcc->dispatch_list = llist_del_all(&fcc->issue_list);
298                 fcc->dispatch_list = llist_reverse_order(fcc->dispatch_list);
299
300                 bio->bi_bdev = sbi->sb->s_bdev;
301                 ret = submit_bio_wait(WRITE_FLUSH, bio);
302
303                 llist_for_each_entry_safe(cmd, next,
304                                           fcc->dispatch_list, llnode) {
305                         cmd->ret = ret;
306                         complete(&cmd->wait);
307                 }
308                 bio_put(bio);
309                 fcc->dispatch_list = NULL;
310         }
311
312         wait_event_interruptible(*q,
313                 kthread_should_stop() || !llist_empty(&fcc->issue_list));
314         goto repeat;
315 }
316
317 int f2fs_issue_flush(struct f2fs_sb_info *sbi)
318 {
319         struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
320         struct flush_cmd cmd;
321
322         trace_f2fs_issue_flush(sbi->sb, test_opt(sbi, NOBARRIER),
323                                         test_opt(sbi, FLUSH_MERGE));
324
325         if (test_opt(sbi, NOBARRIER))
326                 return 0;
327
328         if (!test_opt(sbi, FLUSH_MERGE))
329                 return blkdev_issue_flush(sbi->sb->s_bdev, GFP_KERNEL, NULL);
330
331         init_completion(&cmd.wait);
332
333         llist_add(&cmd.llnode, &fcc->issue_list);
334
335         if (!fcc->dispatch_list)
336                 wake_up(&fcc->flush_wait_queue);
337
338         wait_for_completion(&cmd.wait);
339
340         return cmd.ret;
341 }
342
343 int create_flush_cmd_control(struct f2fs_sb_info *sbi)
344 {
345         dev_t dev = sbi->sb->s_bdev->bd_dev;
346         struct flush_cmd_control *fcc;
347         int err = 0;
348
349         fcc = kzalloc(sizeof(struct flush_cmd_control), GFP_KERNEL);
350         if (!fcc)
351                 return -ENOMEM;
352         init_waitqueue_head(&fcc->flush_wait_queue);
353         init_llist_head(&fcc->issue_list);
354         SM_I(sbi)->cmd_control_info = fcc;
355         fcc->f2fs_issue_flush = kthread_run(issue_flush_thread, sbi,
356                                 "f2fs_flush-%u:%u", MAJOR(dev), MINOR(dev));
357         if (IS_ERR(fcc->f2fs_issue_flush)) {
358                 err = PTR_ERR(fcc->f2fs_issue_flush);
359                 kfree(fcc);
360                 SM_I(sbi)->cmd_control_info = NULL;
361                 return err;
362         }
363
364         return err;
365 }
366
367 void destroy_flush_cmd_control(struct f2fs_sb_info *sbi)
368 {
369         struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
370
371         if (fcc && fcc->f2fs_issue_flush)
372                 kthread_stop(fcc->f2fs_issue_flush);
373         kfree(fcc);
374         SM_I(sbi)->cmd_control_info = NULL;
375 }
376
377 static void __locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
378                 enum dirty_type dirty_type)
379 {
380         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
381
382         /* need not be added */
383         if (IS_CURSEG(sbi, segno))
384                 return;
385
386         if (!test_and_set_bit(segno, dirty_i->dirty_segmap[dirty_type]))
387                 dirty_i->nr_dirty[dirty_type]++;
388
389         if (dirty_type == DIRTY) {
390                 struct seg_entry *sentry = get_seg_entry(sbi, segno);
391                 enum dirty_type t = sentry->type;
392
393                 if (unlikely(t >= DIRTY)) {
394                         f2fs_bug_on(sbi, 1);
395                         return;
396                 }
397                 if (!test_and_set_bit(segno, dirty_i->dirty_segmap[t]))
398                         dirty_i->nr_dirty[t]++;
399         }
400 }
401
402 static void __remove_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
403                 enum dirty_type dirty_type)
404 {
405         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
406
407         if (test_and_clear_bit(segno, dirty_i->dirty_segmap[dirty_type]))
408                 dirty_i->nr_dirty[dirty_type]--;
409
410         if (dirty_type == DIRTY) {
411                 struct seg_entry *sentry = get_seg_entry(sbi, segno);
412                 enum dirty_type t = sentry->type;
413
414                 if (test_and_clear_bit(segno, dirty_i->dirty_segmap[t]))
415                         dirty_i->nr_dirty[t]--;
416
417                 if (get_valid_blocks(sbi, segno, sbi->segs_per_sec) == 0)
418                         clear_bit(GET_SECNO(sbi, segno),
419                                                 dirty_i->victim_secmap);
420         }
421 }
422
423 /*
424  * Should not occur error such as -ENOMEM.
425  * Adding dirty entry into seglist is not critical operation.
426  * If a given segment is one of current working segments, it won't be added.
427  */
428 static void locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno)
429 {
430         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
431         unsigned short valid_blocks;
432
433         if (segno == NULL_SEGNO || IS_CURSEG(sbi, segno))
434                 return;
435
436         mutex_lock(&dirty_i->seglist_lock);
437
438         valid_blocks = get_valid_blocks(sbi, segno, 0);
439
440         if (valid_blocks == 0) {
441                 __locate_dirty_segment(sbi, segno, PRE);
442                 __remove_dirty_segment(sbi, segno, DIRTY);
443         } else if (valid_blocks < sbi->blocks_per_seg) {
444                 __locate_dirty_segment(sbi, segno, DIRTY);
445         } else {
446                 /* Recovery routine with SSR needs this */
447                 __remove_dirty_segment(sbi, segno, DIRTY);
448         }
449
450         mutex_unlock(&dirty_i->seglist_lock);
451 }
452
453 static int f2fs_issue_discard(struct f2fs_sb_info *sbi,
454                                 block_t blkstart, block_t blklen)
455 {
456         sector_t start = SECTOR_FROM_BLOCK(blkstart);
457         sector_t len = SECTOR_FROM_BLOCK(blklen);
458         trace_f2fs_issue_discard(sbi->sb, blkstart, blklen);
459         return blkdev_issue_discard(sbi->sb->s_bdev, start, len, GFP_NOFS, 0);
460 }
461
462 void discard_next_dnode(struct f2fs_sb_info *sbi, block_t blkaddr)
463 {
464         if (f2fs_issue_discard(sbi, blkaddr, 1)) {
465                 struct page *page = grab_meta_page(sbi, blkaddr);
466                 /* zero-filled page */
467                 set_page_dirty(page);
468                 f2fs_put_page(page, 1);
469         }
470 }
471
472 static void add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc)
473 {
474         struct list_head *head = &SM_I(sbi)->discard_list;
475         struct discard_entry *new;
476         int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
477         int max_blocks = sbi->blocks_per_seg;
478         struct seg_entry *se = get_seg_entry(sbi, cpc->trim_start);
479         unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
480         unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
481         unsigned long dmap[entries];
482         unsigned int start = 0, end = -1;
483         bool force = (cpc->reason == CP_DISCARD);
484         int i;
485
486         if (!force && !test_opt(sbi, DISCARD))
487                 return;
488
489         if (force && !se->valid_blocks) {
490                 struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
491                 /*
492                  * if this segment is registered in the prefree list, then
493                  * we should skip adding a discard candidate, and let the
494                  * checkpoint do that later.
495                  */
496                 mutex_lock(&dirty_i->seglist_lock);
497                 if (test_bit(cpc->trim_start, dirty_i->dirty_segmap[PRE])) {
498                         mutex_unlock(&dirty_i->seglist_lock);
499                         cpc->trimmed += sbi->blocks_per_seg;
500                         return;
501                 }
502                 mutex_unlock(&dirty_i->seglist_lock);
503
504                 new = f2fs_kmem_cache_alloc(discard_entry_slab, GFP_NOFS);
505                 INIT_LIST_HEAD(&new->list);
506                 new->blkaddr = START_BLOCK(sbi, cpc->trim_start);
507                 new->len = sbi->blocks_per_seg;
508                 list_add_tail(&new->list, head);
509                 SM_I(sbi)->nr_discards += sbi->blocks_per_seg;
510                 cpc->trimmed += sbi->blocks_per_seg;
511                 return;
512         }
513
514         /* zero block will be discarded through the prefree list */
515         if (!se->valid_blocks || se->valid_blocks == max_blocks)
516                 return;
517
518         /* SIT_VBLOCK_MAP_SIZE should be multiple of sizeof(unsigned long) */
519         for (i = 0; i < entries; i++)
520                 dmap[i] = (cur_map[i] ^ ckpt_map[i]) & ckpt_map[i];
521
522         while (force || SM_I(sbi)->nr_discards <= SM_I(sbi)->max_discards) {
523                 start = __find_rev_next_bit(dmap, max_blocks, end + 1);
524                 if (start >= max_blocks)
525                         break;
526
527                 end = __find_rev_next_zero_bit(dmap, max_blocks, start + 1);
528
529                 if (end - start < cpc->trim_minlen)
530                         continue;
531
532                 new = f2fs_kmem_cache_alloc(discard_entry_slab, GFP_NOFS);
533                 INIT_LIST_HEAD(&new->list);
534                 new->blkaddr = START_BLOCK(sbi, cpc->trim_start) + start;
535                 new->len = end - start;
536                 cpc->trimmed += end - start;
537
538                 list_add_tail(&new->list, head);
539                 SM_I(sbi)->nr_discards += end - start;
540         }
541 }
542
543 void release_discard_addrs(struct f2fs_sb_info *sbi)
544 {
545         struct list_head *head = &(SM_I(sbi)->discard_list);
546         struct discard_entry *entry, *this;
547
548         /* drop caches */
549         list_for_each_entry_safe(entry, this, head, list) {
550                 list_del(&entry->list);
551                 kmem_cache_free(discard_entry_slab, entry);
552         }
553 }
554
555 /*
556  * Should call clear_prefree_segments after checkpoint is done.
557  */
558 static void set_prefree_as_free_segments(struct f2fs_sb_info *sbi)
559 {
560         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
561         unsigned int segno;
562
563         mutex_lock(&dirty_i->seglist_lock);
564         for_each_set_bit(segno, dirty_i->dirty_segmap[PRE], MAIN_SEGS(sbi))
565                 __set_test_and_free(sbi, segno);
566         mutex_unlock(&dirty_i->seglist_lock);
567 }
568
569 void clear_prefree_segments(struct f2fs_sb_info *sbi)
570 {
571         struct list_head *head = &(SM_I(sbi)->discard_list);
572         struct discard_entry *entry, *this;
573         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
574         unsigned long *prefree_map = dirty_i->dirty_segmap[PRE];
575         unsigned int start = 0, end = -1;
576
577         mutex_lock(&dirty_i->seglist_lock);
578
579         while (1) {
580                 int i;
581                 start = find_next_bit(prefree_map, MAIN_SEGS(sbi), end + 1);
582                 if (start >= MAIN_SEGS(sbi))
583                         break;
584                 end = find_next_zero_bit(prefree_map, MAIN_SEGS(sbi),
585                                                                 start + 1);
586
587                 for (i = start; i < end; i++)
588                         clear_bit(i, prefree_map);
589
590                 dirty_i->nr_dirty[PRE] -= end - start;
591
592                 if (!test_opt(sbi, DISCARD))
593                         continue;
594
595                 f2fs_issue_discard(sbi, START_BLOCK(sbi, start),
596                                 (end - start) << sbi->log_blocks_per_seg);
597         }
598         mutex_unlock(&dirty_i->seglist_lock);
599
600         /* send small discards */
601         list_for_each_entry_safe(entry, this, head, list) {
602                 f2fs_issue_discard(sbi, entry->blkaddr, entry->len);
603                 list_del(&entry->list);
604                 SM_I(sbi)->nr_discards -= entry->len;
605                 kmem_cache_free(discard_entry_slab, entry);
606         }
607 }
608
609 static bool __mark_sit_entry_dirty(struct f2fs_sb_info *sbi, unsigned int segno)
610 {
611         struct sit_info *sit_i = SIT_I(sbi);
612
613         if (!__test_and_set_bit(segno, sit_i->dirty_sentries_bitmap)) {
614                 sit_i->dirty_sentries++;
615                 return false;
616         }
617
618         return true;
619 }
620
621 static void __set_sit_entry_type(struct f2fs_sb_info *sbi, int type,
622                                         unsigned int segno, int modified)
623 {
624         struct seg_entry *se = get_seg_entry(sbi, segno);
625         se->type = type;
626         if (modified)
627                 __mark_sit_entry_dirty(sbi, segno);
628 }
629
630 static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
631 {
632         struct seg_entry *se;
633         unsigned int segno, offset;
634         long int new_vblocks;
635
636         segno = GET_SEGNO(sbi, blkaddr);
637
638         se = get_seg_entry(sbi, segno);
639         new_vblocks = se->valid_blocks + del;
640         offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
641
642         f2fs_bug_on(sbi, (new_vblocks >> (sizeof(unsigned short) << 3) ||
643                                 (new_vblocks > sbi->blocks_per_seg)));
644
645         se->valid_blocks = new_vblocks;
646         se->mtime = get_mtime(sbi);
647         SIT_I(sbi)->max_mtime = se->mtime;
648
649         /* Update valid block bitmap */
650         if (del > 0) {
651                 if (f2fs_set_bit(offset, se->cur_valid_map))
652                         f2fs_bug_on(sbi, 1);
653         } else {
654                 if (!f2fs_clear_bit(offset, se->cur_valid_map))
655                         f2fs_bug_on(sbi, 1);
656         }
657         if (!f2fs_test_bit(offset, se->ckpt_valid_map))
658                 se->ckpt_valid_blocks += del;
659
660         __mark_sit_entry_dirty(sbi, segno);
661
662         /* update total number of valid blocks to be written in ckpt area */
663         SIT_I(sbi)->written_valid_blocks += del;
664
665         if (sbi->segs_per_sec > 1)
666                 get_sec_entry(sbi, segno)->valid_blocks += del;
667 }
668
669 void refresh_sit_entry(struct f2fs_sb_info *sbi, block_t old, block_t new)
670 {
671         update_sit_entry(sbi, new, 1);
672         if (GET_SEGNO(sbi, old) != NULL_SEGNO)
673                 update_sit_entry(sbi, old, -1);
674
675         locate_dirty_segment(sbi, GET_SEGNO(sbi, old));
676         locate_dirty_segment(sbi, GET_SEGNO(sbi, new));
677 }
678
679 void invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr)
680 {
681         unsigned int segno = GET_SEGNO(sbi, addr);
682         struct sit_info *sit_i = SIT_I(sbi);
683
684         f2fs_bug_on(sbi, addr == NULL_ADDR);
685         if (addr == NEW_ADDR)
686                 return;
687
688         /* add it into sit main buffer */
689         mutex_lock(&sit_i->sentry_lock);
690
691         update_sit_entry(sbi, addr, -1);
692
693         /* add it into dirty seglist */
694         locate_dirty_segment(sbi, segno);
695
696         mutex_unlock(&sit_i->sentry_lock);
697 }
698
699 /*
700  * This function should be resided under the curseg_mutex lock
701  */
702 static void __add_sum_entry(struct f2fs_sb_info *sbi, int type,
703                                         struct f2fs_summary *sum)
704 {
705         struct curseg_info *curseg = CURSEG_I(sbi, type);
706         void *addr = curseg->sum_blk;
707         addr += curseg->next_blkoff * sizeof(struct f2fs_summary);
708         memcpy(addr, sum, sizeof(struct f2fs_summary));
709 }
710
711 /*
712  * Calculate the number of current summary pages for writing
713  */
714 int npages_for_summary_flush(struct f2fs_sb_info *sbi)
715 {
716         int valid_sum_count = 0;
717         int i, sum_in_page;
718
719         for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
720                 if (sbi->ckpt->alloc_type[i] == SSR)
721                         valid_sum_count += sbi->blocks_per_seg;
722                 else
723                         valid_sum_count += curseg_blkoff(sbi, i);
724         }
725
726         sum_in_page = (PAGE_CACHE_SIZE - 2 * SUM_JOURNAL_SIZE -
727                         SUM_FOOTER_SIZE) / SUMMARY_SIZE;
728         if (valid_sum_count <= sum_in_page)
729                 return 1;
730         else if ((valid_sum_count - sum_in_page) <=
731                 (PAGE_CACHE_SIZE - SUM_FOOTER_SIZE) / SUMMARY_SIZE)
732                 return 2;
733         return 3;
734 }
735
736 /*
737  * Caller should put this summary page
738  */
739 struct page *get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno)
740 {
741         return get_meta_page(sbi, GET_SUM_BLOCK(sbi, segno));
742 }
743
744 static void write_sum_page(struct f2fs_sb_info *sbi,
745                         struct f2fs_summary_block *sum_blk, block_t blk_addr)
746 {
747         struct page *page = grab_meta_page(sbi, blk_addr);
748         void *kaddr = page_address(page);
749         memcpy(kaddr, sum_blk, PAGE_CACHE_SIZE);
750         set_page_dirty(page);
751         f2fs_put_page(page, 1);
752 }
753
754 static int is_next_segment_free(struct f2fs_sb_info *sbi, int type)
755 {
756         struct curseg_info *curseg = CURSEG_I(sbi, type);
757         unsigned int segno = curseg->segno + 1;
758         struct free_segmap_info *free_i = FREE_I(sbi);
759
760         if (segno < MAIN_SEGS(sbi) && segno % sbi->segs_per_sec)
761                 return !test_bit(segno, free_i->free_segmap);
762         return 0;
763 }
764
765 /*
766  * Find a new segment from the free segments bitmap to right order
767  * This function should be returned with success, otherwise BUG
768  */
769 static void get_new_segment(struct f2fs_sb_info *sbi,
770                         unsigned int *newseg, bool new_sec, int dir)
771 {
772         struct free_segmap_info *free_i = FREE_I(sbi);
773         unsigned int segno, secno, zoneno;
774         unsigned int total_zones = MAIN_SECS(sbi) / sbi->secs_per_zone;
775         unsigned int hint = *newseg / sbi->segs_per_sec;
776         unsigned int old_zoneno = GET_ZONENO_FROM_SEGNO(sbi, *newseg);
777         unsigned int left_start = hint;
778         bool init = true;
779         int go_left = 0;
780         int i;
781
782         write_lock(&free_i->segmap_lock);
783
784         if (!new_sec && ((*newseg + 1) % sbi->segs_per_sec)) {
785                 segno = find_next_zero_bit(free_i->free_segmap,
786                                         MAIN_SEGS(sbi), *newseg + 1);
787                 if (segno - *newseg < sbi->segs_per_sec -
788                                         (*newseg % sbi->segs_per_sec))
789                         goto got_it;
790         }
791 find_other_zone:
792         secno = find_next_zero_bit(free_i->free_secmap, MAIN_SECS(sbi), hint);
793         if (secno >= MAIN_SECS(sbi)) {
794                 if (dir == ALLOC_RIGHT) {
795                         secno = find_next_zero_bit(free_i->free_secmap,
796                                                         MAIN_SECS(sbi), 0);
797                         f2fs_bug_on(sbi, secno >= MAIN_SECS(sbi));
798                 } else {
799                         go_left = 1;
800                         left_start = hint - 1;
801                 }
802         }
803         if (go_left == 0)
804                 goto skip_left;
805
806         while (test_bit(left_start, free_i->free_secmap)) {
807                 if (left_start > 0) {
808                         left_start--;
809                         continue;
810                 }
811                 left_start = find_next_zero_bit(free_i->free_secmap,
812                                                         MAIN_SECS(sbi), 0);
813                 f2fs_bug_on(sbi, left_start >= MAIN_SECS(sbi));
814                 break;
815         }
816         secno = left_start;
817 skip_left:
818         hint = secno;
819         segno = secno * sbi->segs_per_sec;
820         zoneno = secno / sbi->secs_per_zone;
821
822         /* give up on finding another zone */
823         if (!init)
824                 goto got_it;
825         if (sbi->secs_per_zone == 1)
826                 goto got_it;
827         if (zoneno == old_zoneno)
828                 goto got_it;
829         if (dir == ALLOC_LEFT) {
830                 if (!go_left && zoneno + 1 >= total_zones)
831                         goto got_it;
832                 if (go_left && zoneno == 0)
833                         goto got_it;
834         }
835         for (i = 0; i < NR_CURSEG_TYPE; i++)
836                 if (CURSEG_I(sbi, i)->zone == zoneno)
837                         break;
838
839         if (i < NR_CURSEG_TYPE) {
840                 /* zone is in user, try another */
841                 if (go_left)
842                         hint = zoneno * sbi->secs_per_zone - 1;
843                 else if (zoneno + 1 >= total_zones)
844                         hint = 0;
845                 else
846                         hint = (zoneno + 1) * sbi->secs_per_zone;
847                 init = false;
848                 goto find_other_zone;
849         }
850 got_it:
851         /* set it as dirty segment in free segmap */
852         f2fs_bug_on(sbi, test_bit(segno, free_i->free_segmap));
853         __set_inuse(sbi, segno);
854         *newseg = segno;
855         write_unlock(&free_i->segmap_lock);
856 }
857
858 static void reset_curseg(struct f2fs_sb_info *sbi, int type, int modified)
859 {
860         struct curseg_info *curseg = CURSEG_I(sbi, type);
861         struct summary_footer *sum_footer;
862
863         curseg->segno = curseg->next_segno;
864         curseg->zone = GET_ZONENO_FROM_SEGNO(sbi, curseg->segno);
865         curseg->next_blkoff = 0;
866         curseg->next_segno = NULL_SEGNO;
867
868         sum_footer = &(curseg->sum_blk->footer);
869         memset(sum_footer, 0, sizeof(struct summary_footer));
870         if (IS_DATASEG(type))
871                 SET_SUM_TYPE(sum_footer, SUM_TYPE_DATA);
872         if (IS_NODESEG(type))
873                 SET_SUM_TYPE(sum_footer, SUM_TYPE_NODE);
874         __set_sit_entry_type(sbi, type, curseg->segno, modified);
875 }
876
877 /*
878  * Allocate a current working segment.
879  * This function always allocates a free segment in LFS manner.
880  */
881 static void new_curseg(struct f2fs_sb_info *sbi, int type, bool new_sec)
882 {
883         struct curseg_info *curseg = CURSEG_I(sbi, type);
884         unsigned int segno = curseg->segno;
885         int dir = ALLOC_LEFT;
886
887         write_sum_page(sbi, curseg->sum_blk,
888                                 GET_SUM_BLOCK(sbi, segno));
889         if (type == CURSEG_WARM_DATA || type == CURSEG_COLD_DATA)
890                 dir = ALLOC_RIGHT;
891
892         if (test_opt(sbi, NOHEAP))
893                 dir = ALLOC_RIGHT;
894
895         get_new_segment(sbi, &segno, new_sec, dir);
896         curseg->next_segno = segno;
897         reset_curseg(sbi, type, 1);
898         curseg->alloc_type = LFS;
899 }
900
901 static void __next_free_blkoff(struct f2fs_sb_info *sbi,
902                         struct curseg_info *seg, block_t start)
903 {
904         struct seg_entry *se = get_seg_entry(sbi, seg->segno);
905         int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
906         unsigned long target_map[entries];
907         unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
908         unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
909         int i, pos;
910
911         for (i = 0; i < entries; i++)
912                 target_map[i] = ckpt_map[i] | cur_map[i];
913
914         pos = __find_rev_next_zero_bit(target_map, sbi->blocks_per_seg, start);
915
916         seg->next_blkoff = pos;
917 }
918
919 /*
920  * If a segment is written by LFS manner, next block offset is just obtained
921  * by increasing the current block offset. However, if a segment is written by
922  * SSR manner, next block offset obtained by calling __next_free_blkoff
923  */
924 static void __refresh_next_blkoff(struct f2fs_sb_info *sbi,
925                                 struct curseg_info *seg)
926 {
927         if (seg->alloc_type == SSR)
928                 __next_free_blkoff(sbi, seg, seg->next_blkoff + 1);
929         else
930                 seg->next_blkoff++;
931 }
932
933 /*
934  * This function always allocates a used segment(from dirty seglist) by SSR
935  * manner, so it should recover the existing segment information of valid blocks
936  */
937 static void change_curseg(struct f2fs_sb_info *sbi, int type, bool reuse)
938 {
939         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
940         struct curseg_info *curseg = CURSEG_I(sbi, type);
941         unsigned int new_segno = curseg->next_segno;
942         struct f2fs_summary_block *sum_node;
943         struct page *sum_page;
944
945         write_sum_page(sbi, curseg->sum_blk,
946                                 GET_SUM_BLOCK(sbi, curseg->segno));
947         __set_test_and_inuse(sbi, new_segno);
948
949         mutex_lock(&dirty_i->seglist_lock);
950         __remove_dirty_segment(sbi, new_segno, PRE);
951         __remove_dirty_segment(sbi, new_segno, DIRTY);
952         mutex_unlock(&dirty_i->seglist_lock);
953
954         reset_curseg(sbi, type, 1);
955         curseg->alloc_type = SSR;
956         __next_free_blkoff(sbi, curseg, 0);
957
958         if (reuse) {
959                 sum_page = get_sum_page(sbi, new_segno);
960                 sum_node = (struct f2fs_summary_block *)page_address(sum_page);
961                 memcpy(curseg->sum_blk, sum_node, SUM_ENTRY_SIZE);
962                 f2fs_put_page(sum_page, 1);
963         }
964 }
965
966 static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
967 {
968         struct curseg_info *curseg = CURSEG_I(sbi, type);
969         const struct victim_selection *v_ops = DIRTY_I(sbi)->v_ops;
970
971         if (IS_NODESEG(type) || !has_not_enough_free_secs(sbi, 0))
972                 return v_ops->get_victim(sbi,
973                                 &(curseg)->next_segno, BG_GC, type, SSR);
974
975         /* For data segments, let's do SSR more intensively */
976         for (; type >= CURSEG_HOT_DATA; type--)
977                 if (v_ops->get_victim(sbi, &(curseg)->next_segno,
978                                                 BG_GC, type, SSR))
979                         return 1;
980         return 0;
981 }
982
983 /*
984  * flush out current segment and replace it with new segment
985  * This function should be returned with success, otherwise BUG
986  */
987 static void allocate_segment_by_default(struct f2fs_sb_info *sbi,
988                                                 int type, bool force)
989 {
990         struct curseg_info *curseg = CURSEG_I(sbi, type);
991
992         if (force)
993                 new_curseg(sbi, type, true);
994         else if (type == CURSEG_WARM_NODE)
995                 new_curseg(sbi, type, false);
996         else if (curseg->alloc_type == LFS && is_next_segment_free(sbi, type))
997                 new_curseg(sbi, type, false);
998         else if (need_SSR(sbi) && get_ssr_segment(sbi, type))
999                 change_curseg(sbi, type, true);
1000         else
1001                 new_curseg(sbi, type, false);
1002
1003         stat_inc_seg_type(sbi, curseg);
1004 }
1005
1006 void allocate_new_segments(struct f2fs_sb_info *sbi)
1007 {
1008         struct curseg_info *curseg;
1009         unsigned int old_curseg;
1010         int i;
1011
1012         for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1013                 curseg = CURSEG_I(sbi, i);
1014                 old_curseg = curseg->segno;
1015                 SIT_I(sbi)->s_ops->allocate_segment(sbi, i, true);
1016                 locate_dirty_segment(sbi, old_curseg);
1017         }
1018 }
1019
1020 static const struct segment_allocation default_salloc_ops = {
1021         .allocate_segment = allocate_segment_by_default,
1022 };
1023
1024 int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
1025 {
1026         __u64 start = range->start >> sbi->log_blocksize;
1027         __u64 end = start + (range->len >> sbi->log_blocksize) - 1;
1028         unsigned int start_segno, end_segno;
1029         struct cp_control cpc;
1030
1031         if (range->minlen > SEGMENT_SIZE(sbi) || start >= MAX_BLKADDR(sbi) ||
1032                                                 range->len < sbi->blocksize)
1033                 return -EINVAL;
1034
1035         cpc.trimmed = 0;
1036         if (end <= MAIN_BLKADDR(sbi))
1037                 goto out;
1038
1039         /* start/end segment number in main_area */
1040         start_segno = (start <= MAIN_BLKADDR(sbi)) ? 0 : GET_SEGNO(sbi, start);
1041         end_segno = (end >= MAX_BLKADDR(sbi)) ? MAIN_SEGS(sbi) - 1 :
1042                                                 GET_SEGNO(sbi, end);
1043         cpc.reason = CP_DISCARD;
1044         cpc.trim_start = start_segno;
1045         cpc.trim_end = end_segno;
1046         cpc.trim_minlen = range->minlen >> sbi->log_blocksize;
1047
1048         /* do checkpoint to issue discard commands safely */
1049         write_checkpoint(sbi, &cpc);
1050 out:
1051         range->len = cpc.trimmed << sbi->log_blocksize;
1052         return 0;
1053 }
1054
1055 static bool __has_curseg_space(struct f2fs_sb_info *sbi, int type)
1056 {
1057         struct curseg_info *curseg = CURSEG_I(sbi, type);
1058         if (curseg->next_blkoff < sbi->blocks_per_seg)
1059                 return true;
1060         return false;
1061 }
1062
1063 static int __get_segment_type_2(struct page *page, enum page_type p_type)
1064 {
1065         if (p_type == DATA)
1066                 return CURSEG_HOT_DATA;
1067         else
1068                 return CURSEG_HOT_NODE;
1069 }
1070
1071 static int __get_segment_type_4(struct page *page, enum page_type p_type)
1072 {
1073         if (p_type == DATA) {
1074                 struct inode *inode = page->mapping->host;
1075
1076                 if (S_ISDIR(inode->i_mode))
1077                         return CURSEG_HOT_DATA;
1078                 else
1079                         return CURSEG_COLD_DATA;
1080         } else {
1081                 if (IS_DNODE(page) && !is_cold_node(page))
1082                         return CURSEG_HOT_NODE;
1083                 else
1084                         return CURSEG_COLD_NODE;
1085         }
1086 }
1087
1088 static int __get_segment_type_6(struct page *page, enum page_type p_type)
1089 {
1090         if (p_type == DATA) {
1091                 struct inode *inode = page->mapping->host;
1092
1093                 if (S_ISDIR(inode->i_mode))
1094                         return CURSEG_HOT_DATA;
1095                 else if (is_cold_data(page) || file_is_cold(inode))
1096                         return CURSEG_COLD_DATA;
1097                 else
1098                         return CURSEG_WARM_DATA;
1099         } else {
1100                 if (IS_DNODE(page))
1101                         return is_cold_node(page) ? CURSEG_WARM_NODE :
1102                                                 CURSEG_HOT_NODE;
1103                 else
1104                         return CURSEG_COLD_NODE;
1105         }
1106 }
1107
1108 static int __get_segment_type(struct page *page, enum page_type p_type)
1109 {
1110         switch (F2FS_P_SB(page)->active_logs) {
1111         case 2:
1112                 return __get_segment_type_2(page, p_type);
1113         case 4:
1114                 return __get_segment_type_4(page, p_type);
1115         }
1116         /* NR_CURSEG_TYPE(6) logs by default */
1117         f2fs_bug_on(F2FS_P_SB(page),
1118                 F2FS_P_SB(page)->active_logs != NR_CURSEG_TYPE);
1119         return __get_segment_type_6(page, p_type);
1120 }
1121
1122 void allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
1123                 block_t old_blkaddr, block_t *new_blkaddr,
1124                 struct f2fs_summary *sum, int type)
1125 {
1126         struct sit_info *sit_i = SIT_I(sbi);
1127         struct curseg_info *curseg;
1128
1129         curseg = CURSEG_I(sbi, type);
1130
1131         mutex_lock(&curseg->curseg_mutex);
1132
1133         *new_blkaddr = NEXT_FREE_BLKADDR(sbi, curseg);
1134
1135         /*
1136          * __add_sum_entry should be resided under the curseg_mutex
1137          * because, this function updates a summary entry in the
1138          * current summary block.
1139          */
1140         __add_sum_entry(sbi, type, sum);
1141
1142         mutex_lock(&sit_i->sentry_lock);
1143         __refresh_next_blkoff(sbi, curseg);
1144
1145         stat_inc_block_count(sbi, curseg);
1146
1147         if (!__has_curseg_space(sbi, type))
1148                 sit_i->s_ops->allocate_segment(sbi, type, false);
1149         /*
1150          * SIT information should be updated before segment allocation,
1151          * since SSR needs latest valid block information.
1152          */
1153         refresh_sit_entry(sbi, old_blkaddr, *new_blkaddr);
1154
1155         mutex_unlock(&sit_i->sentry_lock);
1156
1157         if (page && IS_NODESEG(type))
1158                 fill_node_footer_blkaddr(page, NEXT_FREE_BLKADDR(sbi, curseg));
1159
1160         mutex_unlock(&curseg->curseg_mutex);
1161 }
1162
1163 static void do_write_page(struct f2fs_sb_info *sbi, struct page *page,
1164                         block_t old_blkaddr, block_t *new_blkaddr,
1165                         struct f2fs_summary *sum, struct f2fs_io_info *fio)
1166 {
1167         int type = __get_segment_type(page, fio->type);
1168
1169         allocate_data_block(sbi, page, old_blkaddr, new_blkaddr, sum, type);
1170
1171         /* writeout dirty page into bdev */
1172         f2fs_submit_page_mbio(sbi, page, *new_blkaddr, fio);
1173 }
1174
1175 void write_meta_page(struct f2fs_sb_info *sbi, struct page *page)
1176 {
1177         struct f2fs_io_info fio = {
1178                 .type = META,
1179                 .rw = WRITE_SYNC | REQ_META | REQ_PRIO
1180         };
1181
1182         set_page_writeback(page);
1183         f2fs_submit_page_mbio(sbi, page, page->index, &fio);
1184 }
1185
1186 void write_node_page(struct f2fs_sb_info *sbi, struct page *page,
1187                 struct f2fs_io_info *fio,
1188                 unsigned int nid, block_t old_blkaddr, block_t *new_blkaddr)
1189 {
1190         struct f2fs_summary sum;
1191         set_summary(&sum, nid, 0, 0);
1192         do_write_page(sbi, page, old_blkaddr, new_blkaddr, &sum, fio);
1193 }
1194
1195 void write_data_page(struct page *page, struct dnode_of_data *dn,
1196                 block_t *new_blkaddr, struct f2fs_io_info *fio)
1197 {
1198         struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
1199         struct f2fs_summary sum;
1200         struct node_info ni;
1201
1202         f2fs_bug_on(sbi, dn->data_blkaddr == NULL_ADDR);
1203         get_node_info(sbi, dn->nid, &ni);
1204         set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
1205
1206         do_write_page(sbi, page, dn->data_blkaddr, new_blkaddr, &sum, fio);
1207 }
1208
1209 void rewrite_data_page(struct page *page, block_t old_blkaddr,
1210                                         struct f2fs_io_info *fio)
1211 {
1212         f2fs_submit_page_mbio(F2FS_P_SB(page), page, old_blkaddr, fio);
1213 }
1214
1215 void recover_data_page(struct f2fs_sb_info *sbi,
1216                         struct page *page, struct f2fs_summary *sum,
1217                         block_t old_blkaddr, block_t new_blkaddr)
1218 {
1219         struct sit_info *sit_i = SIT_I(sbi);
1220         struct curseg_info *curseg;
1221         unsigned int segno, old_cursegno;
1222         struct seg_entry *se;
1223         int type;
1224
1225         segno = GET_SEGNO(sbi, new_blkaddr);
1226         se = get_seg_entry(sbi, segno);
1227         type = se->type;
1228
1229         if (se->valid_blocks == 0 && !IS_CURSEG(sbi, segno)) {
1230                 if (old_blkaddr == NULL_ADDR)
1231                         type = CURSEG_COLD_DATA;
1232                 else
1233                         type = CURSEG_WARM_DATA;
1234         }
1235         curseg = CURSEG_I(sbi, type);
1236
1237         mutex_lock(&curseg->curseg_mutex);
1238         mutex_lock(&sit_i->sentry_lock);
1239
1240         old_cursegno = curseg->segno;
1241
1242         /* change the current segment */
1243         if (segno != curseg->segno) {
1244                 curseg->next_segno = segno;
1245                 change_curseg(sbi, type, true);
1246         }
1247
1248         curseg->next_blkoff = GET_BLKOFF_FROM_SEG0(sbi, new_blkaddr);
1249         __add_sum_entry(sbi, type, sum);
1250
1251         refresh_sit_entry(sbi, old_blkaddr, new_blkaddr);
1252         locate_dirty_segment(sbi, old_cursegno);
1253
1254         mutex_unlock(&sit_i->sentry_lock);
1255         mutex_unlock(&curseg->curseg_mutex);
1256 }
1257
1258 static inline bool is_merged_page(struct f2fs_sb_info *sbi,
1259                                         struct page *page, enum page_type type)
1260 {
1261         enum page_type btype = PAGE_TYPE_OF_BIO(type);
1262         struct f2fs_bio_info *io = &sbi->write_io[btype];
1263         struct bio_vec *bvec;
1264         int i;
1265
1266         down_read(&io->io_rwsem);
1267         if (!io->bio)
1268                 goto out;
1269
1270         bio_for_each_segment_all(bvec, io->bio, i) {
1271                 if (page == bvec->bv_page) {
1272                         up_read(&io->io_rwsem);
1273                         return true;
1274                 }
1275         }
1276
1277 out:
1278         up_read(&io->io_rwsem);
1279         return false;
1280 }
1281
1282 void f2fs_wait_on_page_writeback(struct page *page,
1283                                 enum page_type type)
1284 {
1285         if (PageWriteback(page)) {
1286                 struct f2fs_sb_info *sbi = F2FS_P_SB(page);
1287
1288                 if (is_merged_page(sbi, page, type))
1289                         f2fs_submit_merged_bio(sbi, type, WRITE);
1290                 wait_on_page_writeback(page);
1291         }
1292 }
1293
1294 static int read_compacted_summaries(struct f2fs_sb_info *sbi)
1295 {
1296         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1297         struct curseg_info *seg_i;
1298         unsigned char *kaddr;
1299         struct page *page;
1300         block_t start;
1301         int i, j, offset;
1302
1303         start = start_sum_block(sbi);
1304
1305         page = get_meta_page(sbi, start++);
1306         kaddr = (unsigned char *)page_address(page);
1307
1308         /* Step 1: restore nat cache */
1309         seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
1310         memcpy(&seg_i->sum_blk->n_nats, kaddr, SUM_JOURNAL_SIZE);
1311
1312         /* Step 2: restore sit cache */
1313         seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
1314         memcpy(&seg_i->sum_blk->n_sits, kaddr + SUM_JOURNAL_SIZE,
1315                                                 SUM_JOURNAL_SIZE);
1316         offset = 2 * SUM_JOURNAL_SIZE;
1317
1318         /* Step 3: restore summary entries */
1319         for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1320                 unsigned short blk_off;
1321                 unsigned int segno;
1322
1323                 seg_i = CURSEG_I(sbi, i);
1324                 segno = le32_to_cpu(ckpt->cur_data_segno[i]);
1325                 blk_off = le16_to_cpu(ckpt->cur_data_blkoff[i]);
1326                 seg_i->next_segno = segno;
1327                 reset_curseg(sbi, i, 0);
1328                 seg_i->alloc_type = ckpt->alloc_type[i];
1329                 seg_i->next_blkoff = blk_off;
1330
1331                 if (seg_i->alloc_type == SSR)
1332                         blk_off = sbi->blocks_per_seg;
1333
1334                 for (j = 0; j < blk_off; j++) {
1335                         struct f2fs_summary *s;
1336                         s = (struct f2fs_summary *)(kaddr + offset);
1337                         seg_i->sum_blk->entries[j] = *s;
1338                         offset += SUMMARY_SIZE;
1339                         if (offset + SUMMARY_SIZE <= PAGE_CACHE_SIZE -
1340                                                 SUM_FOOTER_SIZE)
1341                                 continue;
1342
1343                         f2fs_put_page(page, 1);
1344                         page = NULL;
1345
1346                         page = get_meta_page(sbi, start++);
1347                         kaddr = (unsigned char *)page_address(page);
1348                         offset = 0;
1349                 }
1350         }
1351         f2fs_put_page(page, 1);
1352         return 0;
1353 }
1354
1355 static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
1356 {
1357         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1358         struct f2fs_summary_block *sum;
1359         struct curseg_info *curseg;
1360         struct page *new;
1361         unsigned short blk_off;
1362         unsigned int segno = 0;
1363         block_t blk_addr = 0;
1364
1365         /* get segment number and block addr */
1366         if (IS_DATASEG(type)) {
1367                 segno = le32_to_cpu(ckpt->cur_data_segno[type]);
1368                 blk_off = le16_to_cpu(ckpt->cur_data_blkoff[type -
1369                                                         CURSEG_HOT_DATA]);
1370                 if (is_set_ckpt_flags(ckpt, CP_UMOUNT_FLAG))
1371                         blk_addr = sum_blk_addr(sbi, NR_CURSEG_TYPE, type);
1372                 else
1373                         blk_addr = sum_blk_addr(sbi, NR_CURSEG_DATA_TYPE, type);
1374         } else {
1375                 segno = le32_to_cpu(ckpt->cur_node_segno[type -
1376                                                         CURSEG_HOT_NODE]);
1377                 blk_off = le16_to_cpu(ckpt->cur_node_blkoff[type -
1378                                                         CURSEG_HOT_NODE]);
1379                 if (is_set_ckpt_flags(ckpt, CP_UMOUNT_FLAG))
1380                         blk_addr = sum_blk_addr(sbi, NR_CURSEG_NODE_TYPE,
1381                                                         type - CURSEG_HOT_NODE);
1382                 else
1383                         blk_addr = GET_SUM_BLOCK(sbi, segno);
1384         }
1385
1386         new = get_meta_page(sbi, blk_addr);
1387         sum = (struct f2fs_summary_block *)page_address(new);
1388
1389         if (IS_NODESEG(type)) {
1390                 if (is_set_ckpt_flags(ckpt, CP_UMOUNT_FLAG)) {
1391                         struct f2fs_summary *ns = &sum->entries[0];
1392                         int i;
1393                         for (i = 0; i < sbi->blocks_per_seg; i++, ns++) {
1394                                 ns->version = 0;
1395                                 ns->ofs_in_node = 0;
1396                         }
1397                 } else {
1398                         int err;
1399
1400                         err = restore_node_summary(sbi, segno, sum);
1401                         if (err) {
1402                                 f2fs_put_page(new, 1);
1403                                 return err;
1404                         }
1405                 }
1406         }
1407
1408         /* set uncompleted segment to curseg */
1409         curseg = CURSEG_I(sbi, type);
1410         mutex_lock(&curseg->curseg_mutex);
1411         memcpy(curseg->sum_blk, sum, PAGE_CACHE_SIZE);
1412         curseg->next_segno = segno;
1413         reset_curseg(sbi, type, 0);
1414         curseg->alloc_type = ckpt->alloc_type[type];
1415         curseg->next_blkoff = blk_off;
1416         mutex_unlock(&curseg->curseg_mutex);
1417         f2fs_put_page(new, 1);
1418         return 0;
1419 }
1420
1421 static int restore_curseg_summaries(struct f2fs_sb_info *sbi)
1422 {
1423         int type = CURSEG_HOT_DATA;
1424         int err;
1425
1426         if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_COMPACT_SUM_FLAG)) {
1427                 /* restore for compacted data summary */
1428                 if (read_compacted_summaries(sbi))
1429                         return -EINVAL;
1430                 type = CURSEG_HOT_NODE;
1431         }
1432
1433         for (; type <= CURSEG_COLD_NODE; type++) {
1434                 err = read_normal_summaries(sbi, type);
1435                 if (err)
1436                         return err;
1437         }
1438
1439         return 0;
1440 }
1441
1442 static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr)
1443 {
1444         struct page *page;
1445         unsigned char *kaddr;
1446         struct f2fs_summary *summary;
1447         struct curseg_info *seg_i;
1448         int written_size = 0;
1449         int i, j;
1450
1451         page = grab_meta_page(sbi, blkaddr++);
1452         kaddr = (unsigned char *)page_address(page);
1453
1454         /* Step 1: write nat cache */
1455         seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
1456         memcpy(kaddr, &seg_i->sum_blk->n_nats, SUM_JOURNAL_SIZE);
1457         written_size += SUM_JOURNAL_SIZE;
1458
1459         /* Step 2: write sit cache */
1460         seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
1461         memcpy(kaddr + written_size, &seg_i->sum_blk->n_sits,
1462                                                 SUM_JOURNAL_SIZE);
1463         written_size += SUM_JOURNAL_SIZE;
1464
1465         /* Step 3: write summary entries */
1466         for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1467                 unsigned short blkoff;
1468                 seg_i = CURSEG_I(sbi, i);
1469                 if (sbi->ckpt->alloc_type[i] == SSR)
1470                         blkoff = sbi->blocks_per_seg;
1471                 else
1472                         blkoff = curseg_blkoff(sbi, i);
1473
1474                 for (j = 0; j < blkoff; j++) {
1475                         if (!page) {
1476                                 page = grab_meta_page(sbi, blkaddr++);
1477                                 kaddr = (unsigned char *)page_address(page);
1478                                 written_size = 0;
1479                         }
1480                         summary = (struct f2fs_summary *)(kaddr + written_size);
1481                         *summary = seg_i->sum_blk->entries[j];
1482                         written_size += SUMMARY_SIZE;
1483
1484                         if (written_size + SUMMARY_SIZE <= PAGE_CACHE_SIZE -
1485                                                         SUM_FOOTER_SIZE)
1486                                 continue;
1487
1488                         set_page_dirty(page);
1489                         f2fs_put_page(page, 1);
1490                         page = NULL;
1491                 }
1492         }
1493         if (page) {
1494                 set_page_dirty(page);
1495                 f2fs_put_page(page, 1);
1496         }
1497 }
1498
1499 static void write_normal_summaries(struct f2fs_sb_info *sbi,
1500                                         block_t blkaddr, int type)
1501 {
1502         int i, end;
1503         if (IS_DATASEG(type))
1504                 end = type + NR_CURSEG_DATA_TYPE;
1505         else
1506                 end = type + NR_CURSEG_NODE_TYPE;
1507
1508         for (i = type; i < end; i++) {
1509                 struct curseg_info *sum = CURSEG_I(sbi, i);
1510                 mutex_lock(&sum->curseg_mutex);
1511                 write_sum_page(sbi, sum->sum_blk, blkaddr + (i - type));
1512                 mutex_unlock(&sum->curseg_mutex);
1513         }
1514 }
1515
1516 void write_data_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
1517 {
1518         if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_COMPACT_SUM_FLAG))
1519                 write_compacted_summaries(sbi, start_blk);
1520         else
1521                 write_normal_summaries(sbi, start_blk, CURSEG_HOT_DATA);
1522 }
1523
1524 void write_node_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
1525 {
1526         if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_UMOUNT_FLAG))
1527                 write_normal_summaries(sbi, start_blk, CURSEG_HOT_NODE);
1528 }
1529
1530 int lookup_journal_in_cursum(struct f2fs_summary_block *sum, int type,
1531                                         unsigned int val, int alloc)
1532 {
1533         int i;
1534
1535         if (type == NAT_JOURNAL) {
1536                 for (i = 0; i < nats_in_cursum(sum); i++) {
1537                         if (le32_to_cpu(nid_in_journal(sum, i)) == val)
1538                                 return i;
1539                 }
1540                 if (alloc && nats_in_cursum(sum) < NAT_JOURNAL_ENTRIES)
1541                         return update_nats_in_cursum(sum, 1);
1542         } else if (type == SIT_JOURNAL) {
1543                 for (i = 0; i < sits_in_cursum(sum); i++)
1544                         if (le32_to_cpu(segno_in_journal(sum, i)) == val)
1545                                 return i;
1546                 if (alloc && sits_in_cursum(sum) < SIT_JOURNAL_ENTRIES)
1547                         return update_sits_in_cursum(sum, 1);
1548         }
1549         return -1;
1550 }
1551
1552 static struct page *get_current_sit_page(struct f2fs_sb_info *sbi,
1553                                         unsigned int segno)
1554 {
1555         struct sit_info *sit_i = SIT_I(sbi);
1556         unsigned int offset = SIT_BLOCK_OFFSET(segno);
1557         block_t blk_addr = sit_i->sit_base_addr + offset;
1558
1559         check_seg_range(sbi, segno);
1560
1561         /* calculate sit block address */
1562         if (f2fs_test_bit(offset, sit_i->sit_bitmap))
1563                 blk_addr += sit_i->sit_blocks;
1564
1565         return get_meta_page(sbi, blk_addr);
1566 }
1567
1568 static struct page *get_next_sit_page(struct f2fs_sb_info *sbi,
1569                                         unsigned int start)
1570 {
1571         struct sit_info *sit_i = SIT_I(sbi);
1572         struct page *src_page, *dst_page;
1573         pgoff_t src_off, dst_off;
1574         void *src_addr, *dst_addr;
1575
1576         src_off = current_sit_addr(sbi, start);
1577         dst_off = next_sit_addr(sbi, src_off);
1578
1579         /* get current sit block page without lock */
1580         src_page = get_meta_page(sbi, src_off);
1581         dst_page = grab_meta_page(sbi, dst_off);
1582         f2fs_bug_on(sbi, PageDirty(src_page));
1583
1584         src_addr = page_address(src_page);
1585         dst_addr = page_address(dst_page);
1586         memcpy(dst_addr, src_addr, PAGE_CACHE_SIZE);
1587
1588         set_page_dirty(dst_page);
1589         f2fs_put_page(src_page, 1);
1590
1591         set_to_next_sit(sit_i, start);
1592
1593         return dst_page;
1594 }
1595
1596 static struct sit_entry_set *grab_sit_entry_set(void)
1597 {
1598         struct sit_entry_set *ses =
1599                         f2fs_kmem_cache_alloc(sit_entry_set_slab, GFP_ATOMIC);
1600
1601         ses->entry_cnt = 0;
1602         INIT_LIST_HEAD(&ses->set_list);
1603         return ses;
1604 }
1605
1606 static void release_sit_entry_set(struct sit_entry_set *ses)
1607 {
1608         list_del(&ses->set_list);
1609         kmem_cache_free(sit_entry_set_slab, ses);
1610 }
1611
1612 static void adjust_sit_entry_set(struct sit_entry_set *ses,
1613                                                 struct list_head *head)
1614 {
1615         struct sit_entry_set *next = ses;
1616
1617         if (list_is_last(&ses->set_list, head))
1618                 return;
1619
1620         list_for_each_entry_continue(next, head, set_list)
1621                 if (ses->entry_cnt <= next->entry_cnt)
1622                         break;
1623
1624         list_move_tail(&ses->set_list, &next->set_list);
1625 }
1626
1627 static void add_sit_entry(unsigned int segno, struct list_head *head)
1628 {
1629         struct sit_entry_set *ses;
1630         unsigned int start_segno = START_SEGNO(segno);
1631
1632         list_for_each_entry(ses, head, set_list) {
1633                 if (ses->start_segno == start_segno) {
1634                         ses->entry_cnt++;
1635                         adjust_sit_entry_set(ses, head);
1636                         return;
1637                 }
1638         }
1639
1640         ses = grab_sit_entry_set();
1641
1642         ses->start_segno = start_segno;
1643         ses->entry_cnt++;
1644         list_add(&ses->set_list, head);
1645 }
1646
1647 static void add_sits_in_set(struct f2fs_sb_info *sbi)
1648 {
1649         struct f2fs_sm_info *sm_info = SM_I(sbi);
1650         struct list_head *set_list = &sm_info->sit_entry_set;
1651         unsigned long *bitmap = SIT_I(sbi)->dirty_sentries_bitmap;
1652         unsigned int segno;
1653
1654         for_each_set_bit(segno, bitmap, MAIN_SEGS(sbi))
1655                 add_sit_entry(segno, set_list);
1656 }
1657
1658 static void remove_sits_in_journal(struct f2fs_sb_info *sbi)
1659 {
1660         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
1661         struct f2fs_summary_block *sum = curseg->sum_blk;
1662         int i;
1663
1664         for (i = sits_in_cursum(sum) - 1; i >= 0; i--) {
1665                 unsigned int segno;
1666                 bool dirtied;
1667
1668                 segno = le32_to_cpu(segno_in_journal(sum, i));
1669                 dirtied = __mark_sit_entry_dirty(sbi, segno);
1670
1671                 if (!dirtied)
1672                         add_sit_entry(segno, &SM_I(sbi)->sit_entry_set);
1673         }
1674         update_sits_in_cursum(sum, -sits_in_cursum(sum));
1675 }
1676
1677 /*
1678  * CP calls this function, which flushes SIT entries including sit_journal,
1679  * and moves prefree segs to free segs.
1680  */
1681 void flush_sit_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1682 {
1683         struct sit_info *sit_i = SIT_I(sbi);
1684         unsigned long *bitmap = sit_i->dirty_sentries_bitmap;
1685         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
1686         struct f2fs_summary_block *sum = curseg->sum_blk;
1687         struct sit_entry_set *ses, *tmp;
1688         struct list_head *head = &SM_I(sbi)->sit_entry_set;
1689         bool to_journal = true;
1690         struct seg_entry *se;
1691
1692         mutex_lock(&curseg->curseg_mutex);
1693         mutex_lock(&sit_i->sentry_lock);
1694
1695         /*
1696          * add and account sit entries of dirty bitmap in sit entry
1697          * set temporarily
1698          */
1699         add_sits_in_set(sbi);
1700
1701         /*
1702          * if there are no enough space in journal to store dirty sit
1703          * entries, remove all entries from journal and add and account
1704          * them in sit entry set.
1705          */
1706         if (!__has_cursum_space(sum, sit_i->dirty_sentries, SIT_JOURNAL))
1707                 remove_sits_in_journal(sbi);
1708
1709         if (!sit_i->dirty_sentries)
1710                 goto out;
1711
1712         /*
1713          * there are two steps to flush sit entries:
1714          * #1, flush sit entries to journal in current cold data summary block.
1715          * #2, flush sit entries to sit page.
1716          */
1717         list_for_each_entry_safe(ses, tmp, head, set_list) {
1718                 struct page *page = NULL;
1719                 struct f2fs_sit_block *raw_sit = NULL;
1720                 unsigned int start_segno = ses->start_segno;
1721                 unsigned int end = min(start_segno + SIT_ENTRY_PER_BLOCK,
1722                                                 (unsigned long)MAIN_SEGS(sbi));
1723                 unsigned int segno = start_segno;
1724
1725                 if (to_journal &&
1726                         !__has_cursum_space(sum, ses->entry_cnt, SIT_JOURNAL))
1727                         to_journal = false;
1728
1729                 if (!to_journal) {
1730                         page = get_next_sit_page(sbi, start_segno);
1731                         raw_sit = page_address(page);
1732                 }
1733
1734                 /* flush dirty sit entries in region of current sit set */
1735                 for_each_set_bit_from(segno, bitmap, end) {
1736                         int offset, sit_offset;
1737
1738                         se = get_seg_entry(sbi, segno);
1739
1740                         /* add discard candidates */
1741                         if (SM_I(sbi)->nr_discards < SM_I(sbi)->max_discards) {
1742                                 cpc->trim_start = segno;
1743                                 add_discard_addrs(sbi, cpc);
1744                         }
1745
1746                         if (to_journal) {
1747                                 offset = lookup_journal_in_cursum(sum,
1748                                                         SIT_JOURNAL, segno, 1);
1749                                 f2fs_bug_on(sbi, offset < 0);
1750                                 segno_in_journal(sum, offset) =
1751                                                         cpu_to_le32(segno);
1752                                 seg_info_to_raw_sit(se,
1753                                                 &sit_in_journal(sum, offset));
1754                         } else {
1755                                 sit_offset = SIT_ENTRY_OFFSET(sit_i, segno);
1756                                 seg_info_to_raw_sit(se,
1757                                                 &raw_sit->entries[sit_offset]);
1758                         }
1759
1760                         __clear_bit(segno, bitmap);
1761                         sit_i->dirty_sentries--;
1762                         ses->entry_cnt--;
1763                 }
1764
1765                 if (!to_journal)
1766                         f2fs_put_page(page, 1);
1767
1768                 f2fs_bug_on(sbi, ses->entry_cnt);
1769                 release_sit_entry_set(ses);
1770         }
1771
1772         f2fs_bug_on(sbi, !list_empty(head));
1773         f2fs_bug_on(sbi, sit_i->dirty_sentries);
1774 out:
1775         if (cpc->reason == CP_DISCARD) {
1776                 for (; cpc->trim_start <= cpc->trim_end; cpc->trim_start++)
1777                         add_discard_addrs(sbi, cpc);
1778         }
1779         mutex_unlock(&sit_i->sentry_lock);
1780         mutex_unlock(&curseg->curseg_mutex);
1781
1782         set_prefree_as_free_segments(sbi);
1783 }
1784
1785 static int build_sit_info(struct f2fs_sb_info *sbi)
1786 {
1787         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
1788         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1789         struct sit_info *sit_i;
1790         unsigned int sit_segs, start;
1791         char *src_bitmap, *dst_bitmap;
1792         unsigned int bitmap_size;
1793
1794         /* allocate memory for SIT information */
1795         sit_i = kzalloc(sizeof(struct sit_info), GFP_KERNEL);
1796         if (!sit_i)
1797                 return -ENOMEM;
1798
1799         SM_I(sbi)->sit_info = sit_i;
1800
1801         sit_i->sentries = vzalloc(MAIN_SEGS(sbi) * sizeof(struct seg_entry));
1802         if (!sit_i->sentries)
1803                 return -ENOMEM;
1804
1805         bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
1806         sit_i->dirty_sentries_bitmap = kzalloc(bitmap_size, GFP_KERNEL);
1807         if (!sit_i->dirty_sentries_bitmap)
1808                 return -ENOMEM;
1809
1810         for (start = 0; start < MAIN_SEGS(sbi); start++) {
1811                 sit_i->sentries[start].cur_valid_map
1812                         = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
1813                 sit_i->sentries[start].ckpt_valid_map
1814                         = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
1815                 if (!sit_i->sentries[start].cur_valid_map
1816                                 || !sit_i->sentries[start].ckpt_valid_map)
1817                         return -ENOMEM;
1818         }
1819
1820         if (sbi->segs_per_sec > 1) {
1821                 sit_i->sec_entries = vzalloc(MAIN_SECS(sbi) *
1822                                         sizeof(struct sec_entry));
1823                 if (!sit_i->sec_entries)
1824                         return -ENOMEM;
1825         }
1826
1827         /* get information related with SIT */
1828         sit_segs = le32_to_cpu(raw_super->segment_count_sit) >> 1;
1829
1830         /* setup SIT bitmap from ckeckpoint pack */
1831         bitmap_size = __bitmap_size(sbi, SIT_BITMAP);
1832         src_bitmap = __bitmap_ptr(sbi, SIT_BITMAP);
1833
1834         dst_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
1835         if (!dst_bitmap)
1836                 return -ENOMEM;
1837
1838         /* init SIT information */
1839         sit_i->s_ops = &default_salloc_ops;
1840
1841         sit_i->sit_base_addr = le32_to_cpu(raw_super->sit_blkaddr);
1842         sit_i->sit_blocks = sit_segs << sbi->log_blocks_per_seg;
1843         sit_i->written_valid_blocks = le64_to_cpu(ckpt->valid_block_count);
1844         sit_i->sit_bitmap = dst_bitmap;
1845         sit_i->bitmap_size = bitmap_size;
1846         sit_i->dirty_sentries = 0;
1847         sit_i->sents_per_block = SIT_ENTRY_PER_BLOCK;
1848         sit_i->elapsed_time = le64_to_cpu(sbi->ckpt->elapsed_time);
1849         sit_i->mounted_time = CURRENT_TIME_SEC.tv_sec;
1850         mutex_init(&sit_i->sentry_lock);
1851         return 0;
1852 }
1853
1854 static int build_free_segmap(struct f2fs_sb_info *sbi)
1855 {
1856         struct free_segmap_info *free_i;
1857         unsigned int bitmap_size, sec_bitmap_size;
1858
1859         /* allocate memory for free segmap information */
1860         free_i = kzalloc(sizeof(struct free_segmap_info), GFP_KERNEL);
1861         if (!free_i)
1862                 return -ENOMEM;
1863
1864         SM_I(sbi)->free_info = free_i;
1865
1866         bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
1867         free_i->free_segmap = kmalloc(bitmap_size, GFP_KERNEL);
1868         if (!free_i->free_segmap)
1869                 return -ENOMEM;
1870
1871         sec_bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
1872         free_i->free_secmap = kmalloc(sec_bitmap_size, GFP_KERNEL);
1873         if (!free_i->free_secmap)
1874                 return -ENOMEM;
1875
1876         /* set all segments as dirty temporarily */
1877         memset(free_i->free_segmap, 0xff, bitmap_size);
1878         memset(free_i->free_secmap, 0xff, sec_bitmap_size);
1879
1880         /* init free segmap information */
1881         free_i->start_segno = GET_SEGNO_FROM_SEG0(sbi, MAIN_BLKADDR(sbi));
1882         free_i->free_segments = 0;
1883         free_i->free_sections = 0;
1884         rwlock_init(&free_i->segmap_lock);
1885         return 0;
1886 }
1887
1888 static int build_curseg(struct f2fs_sb_info *sbi)
1889 {
1890         struct curseg_info *array;
1891         int i;
1892
1893         array = kcalloc(NR_CURSEG_TYPE, sizeof(*array), GFP_KERNEL);
1894         if (!array)
1895                 return -ENOMEM;
1896
1897         SM_I(sbi)->curseg_array = array;
1898
1899         for (i = 0; i < NR_CURSEG_TYPE; i++) {
1900                 mutex_init(&array[i].curseg_mutex);
1901                 array[i].sum_blk = kzalloc(PAGE_CACHE_SIZE, GFP_KERNEL);
1902                 if (!array[i].sum_blk)
1903                         return -ENOMEM;
1904                 array[i].segno = NULL_SEGNO;
1905                 array[i].next_blkoff = 0;
1906         }
1907         return restore_curseg_summaries(sbi);
1908 }
1909
1910 static void build_sit_entries(struct f2fs_sb_info *sbi)
1911 {
1912         struct sit_info *sit_i = SIT_I(sbi);
1913         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
1914         struct f2fs_summary_block *sum = curseg->sum_blk;
1915         int sit_blk_cnt = SIT_BLK_CNT(sbi);
1916         unsigned int i, start, end;
1917         unsigned int readed, start_blk = 0;
1918         int nrpages = MAX_BIO_BLOCKS(sbi);
1919
1920         do {
1921                 readed = ra_meta_pages(sbi, start_blk, nrpages, META_SIT);
1922
1923                 start = start_blk * sit_i->sents_per_block;
1924                 end = (start_blk + readed) * sit_i->sents_per_block;
1925
1926                 for (; start < end && start < MAIN_SEGS(sbi); start++) {
1927                         struct seg_entry *se = &sit_i->sentries[start];
1928                         struct f2fs_sit_block *sit_blk;
1929                         struct f2fs_sit_entry sit;
1930                         struct page *page;
1931
1932                         mutex_lock(&curseg->curseg_mutex);
1933                         for (i = 0; i < sits_in_cursum(sum); i++) {
1934                                 if (le32_to_cpu(segno_in_journal(sum, i))
1935                                                                 == start) {
1936                                         sit = sit_in_journal(sum, i);
1937                                         mutex_unlock(&curseg->curseg_mutex);
1938                                         goto got_it;
1939                                 }
1940                         }
1941                         mutex_unlock(&curseg->curseg_mutex);
1942
1943                         page = get_current_sit_page(sbi, start);
1944                         sit_blk = (struct f2fs_sit_block *)page_address(page);
1945                         sit = sit_blk->entries[SIT_ENTRY_OFFSET(sit_i, start)];
1946                         f2fs_put_page(page, 1);
1947 got_it:
1948                         check_block_count(sbi, start, &sit);
1949                         seg_info_from_raw_sit(se, &sit);
1950                         if (sbi->segs_per_sec > 1) {
1951                                 struct sec_entry *e = get_sec_entry(sbi, start);
1952                                 e->valid_blocks += se->valid_blocks;
1953                         }
1954                 }
1955                 start_blk += readed;
1956         } while (start_blk < sit_blk_cnt);
1957 }
1958
1959 static void init_free_segmap(struct f2fs_sb_info *sbi)
1960 {
1961         unsigned int start;
1962         int type;
1963
1964         for (start = 0; start < MAIN_SEGS(sbi); start++) {
1965                 struct seg_entry *sentry = get_seg_entry(sbi, start);
1966                 if (!sentry->valid_blocks)
1967                         __set_free(sbi, start);
1968         }
1969
1970         /* set use the current segments */
1971         for (type = CURSEG_HOT_DATA; type <= CURSEG_COLD_NODE; type++) {
1972                 struct curseg_info *curseg_t = CURSEG_I(sbi, type);
1973                 __set_test_and_inuse(sbi, curseg_t->segno);
1974         }
1975 }
1976
1977 static void init_dirty_segmap(struct f2fs_sb_info *sbi)
1978 {
1979         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1980         struct free_segmap_info *free_i = FREE_I(sbi);
1981         unsigned int segno = 0, offset = 0;
1982         unsigned short valid_blocks;
1983
1984         while (1) {
1985                 /* find dirty segment based on free segmap */
1986                 segno = find_next_inuse(free_i, MAIN_SEGS(sbi), offset);
1987                 if (segno >= MAIN_SEGS(sbi))
1988                         break;
1989                 offset = segno + 1;
1990                 valid_blocks = get_valid_blocks(sbi, segno, 0);
1991                 if (valid_blocks == sbi->blocks_per_seg || !valid_blocks)
1992                         continue;
1993                 if (valid_blocks > sbi->blocks_per_seg) {
1994                         f2fs_bug_on(sbi, 1);
1995                         continue;
1996                 }
1997                 mutex_lock(&dirty_i->seglist_lock);
1998                 __locate_dirty_segment(sbi, segno, DIRTY);
1999                 mutex_unlock(&dirty_i->seglist_lock);
2000         }
2001 }
2002
2003 static int init_victim_secmap(struct f2fs_sb_info *sbi)
2004 {
2005         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2006         unsigned int bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
2007
2008         dirty_i->victim_secmap = kzalloc(bitmap_size, GFP_KERNEL);
2009         if (!dirty_i->victim_secmap)
2010                 return -ENOMEM;
2011         return 0;
2012 }
2013
2014 static int build_dirty_segmap(struct f2fs_sb_info *sbi)
2015 {
2016         struct dirty_seglist_info *dirty_i;
2017         unsigned int bitmap_size, i;
2018
2019         /* allocate memory for dirty segments list information */
2020         dirty_i = kzalloc(sizeof(struct dirty_seglist_info), GFP_KERNEL);
2021         if (!dirty_i)
2022                 return -ENOMEM;
2023
2024         SM_I(sbi)->dirty_info = dirty_i;
2025         mutex_init(&dirty_i->seglist_lock);
2026
2027         bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
2028
2029         for (i = 0; i < NR_DIRTY_TYPE; i++) {
2030                 dirty_i->dirty_segmap[i] = kzalloc(bitmap_size, GFP_KERNEL);
2031                 if (!dirty_i->dirty_segmap[i])
2032                         return -ENOMEM;
2033         }
2034
2035         init_dirty_segmap(sbi);
2036         return init_victim_secmap(sbi);
2037 }
2038
2039 /*
2040  * Update min, max modified time for cost-benefit GC algorithm
2041  */
2042 static void init_min_max_mtime(struct f2fs_sb_info *sbi)
2043 {
2044         struct sit_info *sit_i = SIT_I(sbi);
2045         unsigned int segno;
2046
2047         mutex_lock(&sit_i->sentry_lock);
2048
2049         sit_i->min_mtime = LLONG_MAX;
2050
2051         for (segno = 0; segno < MAIN_SEGS(sbi); segno += sbi->segs_per_sec) {
2052                 unsigned int i;
2053                 unsigned long long mtime = 0;
2054
2055                 for (i = 0; i < sbi->segs_per_sec; i++)
2056                         mtime += get_seg_entry(sbi, segno + i)->mtime;
2057
2058                 mtime = div_u64(mtime, sbi->segs_per_sec);
2059
2060                 if (sit_i->min_mtime > mtime)
2061                         sit_i->min_mtime = mtime;
2062         }
2063         sit_i->max_mtime = get_mtime(sbi);
2064         mutex_unlock(&sit_i->sentry_lock);
2065 }
2066
2067 int build_segment_manager(struct f2fs_sb_info *sbi)
2068 {
2069         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
2070         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
2071         struct f2fs_sm_info *sm_info;
2072         int err;
2073
2074         sm_info = kzalloc(sizeof(struct f2fs_sm_info), GFP_KERNEL);
2075         if (!sm_info)
2076                 return -ENOMEM;
2077
2078         /* init sm info */
2079         sbi->sm_info = sm_info;
2080         sm_info->seg0_blkaddr = le32_to_cpu(raw_super->segment0_blkaddr);
2081         sm_info->main_blkaddr = le32_to_cpu(raw_super->main_blkaddr);
2082         sm_info->segment_count = le32_to_cpu(raw_super->segment_count);
2083         sm_info->reserved_segments = le32_to_cpu(ckpt->rsvd_segment_count);
2084         sm_info->ovp_segments = le32_to_cpu(ckpt->overprov_segment_count);
2085         sm_info->main_segments = le32_to_cpu(raw_super->segment_count_main);
2086         sm_info->ssa_blkaddr = le32_to_cpu(raw_super->ssa_blkaddr);
2087         sm_info->rec_prefree_segments = sm_info->main_segments *
2088                                         DEF_RECLAIM_PREFREE_SEGMENTS / 100;
2089         sm_info->ipu_policy = 1 << F2FS_IPU_FSYNC;
2090         sm_info->min_ipu_util = DEF_MIN_IPU_UTIL;
2091         sm_info->min_fsync_blocks = DEF_MIN_FSYNC_BLOCKS;
2092
2093         INIT_LIST_HEAD(&sm_info->discard_list);
2094         sm_info->nr_discards = 0;
2095         sm_info->max_discards = 0;
2096
2097         INIT_LIST_HEAD(&sm_info->sit_entry_set);
2098
2099         if (test_opt(sbi, FLUSH_MERGE) && !f2fs_readonly(sbi->sb)) {
2100                 err = create_flush_cmd_control(sbi);
2101                 if (err)
2102                         return err;
2103         }
2104
2105         err = build_sit_info(sbi);
2106         if (err)
2107                 return err;
2108         err = build_free_segmap(sbi);
2109         if (err)
2110                 return err;
2111         err = build_curseg(sbi);
2112         if (err)
2113                 return err;
2114
2115         /* reinit free segmap based on SIT */
2116         build_sit_entries(sbi);
2117
2118         init_free_segmap(sbi);
2119         err = build_dirty_segmap(sbi);
2120         if (err)
2121                 return err;
2122
2123         init_min_max_mtime(sbi);
2124         return 0;
2125 }
2126
2127 static void discard_dirty_segmap(struct f2fs_sb_info *sbi,
2128                 enum dirty_type dirty_type)
2129 {
2130         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2131
2132         mutex_lock(&dirty_i->seglist_lock);
2133         kfree(dirty_i->dirty_segmap[dirty_type]);
2134         dirty_i->nr_dirty[dirty_type] = 0;
2135         mutex_unlock(&dirty_i->seglist_lock);
2136 }
2137
2138 static void destroy_victim_secmap(struct f2fs_sb_info *sbi)
2139 {
2140         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2141         kfree(dirty_i->victim_secmap);
2142 }
2143
2144 static void destroy_dirty_segmap(struct f2fs_sb_info *sbi)
2145 {
2146         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2147         int i;
2148
2149         if (!dirty_i)
2150                 return;
2151
2152         /* discard pre-free/dirty segments list */
2153         for (i = 0; i < NR_DIRTY_TYPE; i++)
2154                 discard_dirty_segmap(sbi, i);
2155
2156         destroy_victim_secmap(sbi);
2157         SM_I(sbi)->dirty_info = NULL;
2158         kfree(dirty_i);
2159 }
2160
2161 static void destroy_curseg(struct f2fs_sb_info *sbi)
2162 {
2163         struct curseg_info *array = SM_I(sbi)->curseg_array;
2164         int i;
2165
2166         if (!array)
2167                 return;
2168         SM_I(sbi)->curseg_array = NULL;
2169         for (i = 0; i < NR_CURSEG_TYPE; i++)
2170                 kfree(array[i].sum_blk);
2171         kfree(array);
2172 }
2173
2174 static void destroy_free_segmap(struct f2fs_sb_info *sbi)
2175 {
2176         struct free_segmap_info *free_i = SM_I(sbi)->free_info;
2177         if (!free_i)
2178                 return;
2179         SM_I(sbi)->free_info = NULL;
2180         kfree(free_i->free_segmap);
2181         kfree(free_i->free_secmap);
2182         kfree(free_i);
2183 }
2184
2185 static void destroy_sit_info(struct f2fs_sb_info *sbi)
2186 {
2187         struct sit_info *sit_i = SIT_I(sbi);
2188         unsigned int start;
2189
2190         if (!sit_i)
2191                 return;
2192
2193         if (sit_i->sentries) {
2194                 for (start = 0; start < MAIN_SEGS(sbi); start++) {
2195                         kfree(sit_i->sentries[start].cur_valid_map);
2196                         kfree(sit_i->sentries[start].ckpt_valid_map);
2197                 }
2198         }
2199         vfree(sit_i->sentries);
2200         vfree(sit_i->sec_entries);
2201         kfree(sit_i->dirty_sentries_bitmap);
2202
2203         SM_I(sbi)->sit_info = NULL;
2204         kfree(sit_i->sit_bitmap);
2205         kfree(sit_i);
2206 }
2207
2208 void destroy_segment_manager(struct f2fs_sb_info *sbi)
2209 {
2210         struct f2fs_sm_info *sm_info = SM_I(sbi);
2211
2212         if (!sm_info)
2213                 return;
2214         destroy_flush_cmd_control(sbi);
2215         destroy_dirty_segmap(sbi);
2216         destroy_curseg(sbi);
2217         destroy_free_segmap(sbi);
2218         destroy_sit_info(sbi);
2219         sbi->sm_info = NULL;
2220         kfree(sm_info);
2221 }
2222
2223 int __init create_segment_manager_caches(void)
2224 {
2225         discard_entry_slab = f2fs_kmem_cache_create("discard_entry",
2226                         sizeof(struct discard_entry));
2227         if (!discard_entry_slab)
2228                 goto fail;
2229
2230         sit_entry_set_slab = f2fs_kmem_cache_create("sit_entry_set",
2231                         sizeof(struct nat_entry_set));
2232         if (!sit_entry_set_slab)
2233                 goto destory_discard_entry;
2234
2235         inmem_entry_slab = f2fs_kmem_cache_create("inmem_page_entry",
2236                         sizeof(struct inmem_pages));
2237         if (!inmem_entry_slab)
2238                 goto destroy_sit_entry_set;
2239         return 0;
2240
2241 destroy_sit_entry_set:
2242         kmem_cache_destroy(sit_entry_set_slab);
2243 destory_discard_entry:
2244         kmem_cache_destroy(discard_entry_slab);
2245 fail:
2246         return -ENOMEM;
2247 }
2248
2249 void destroy_segment_manager_caches(void)
2250 {
2251         kmem_cache_destroy(sit_entry_set_slab);
2252         kmem_cache_destroy(discard_entry_slab);
2253         kmem_cache_destroy(inmem_entry_slab);
2254 }