4 * Copyright (c) 2012 Samsung Electronics Co., Ltd.
5 * http://www.samsung.com/
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.
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>
23 #include <trace/events/f2fs.h>
25 #define __reverse_ffz(x) __reverse_ffs(~(x))
27 static struct kmem_cache
*discard_entry_slab
;
28 static struct kmem_cache
*flush_cmd_slab
;
31 * __reverse_ffs is copied from include/asm-generic/bitops/__ffs.h since
32 * MSB and LSB are reversed in a byte by f2fs_set_bit.
34 static inline unsigned long __reverse_ffs(unsigned long word
)
38 #if BITS_PER_LONG == 64
39 if ((word
& 0xffffffff) == 0) {
44 if ((word
& 0xffff) == 0) {
48 if ((word
& 0xff) == 0) {
52 if ((word
& 0xf0) == 0)
56 if ((word
& 0xc) == 0)
60 if ((word
& 0x2) == 0)
66 * __find_rev_next(_zero)_bit is copied from lib/find_next_bit.c becasue
67 * f2fs_set_bit makes MSB and LSB reversed in a byte.
70 * f2fs_set_bit(0, bitmap) => 0000 0001
71 * f2fs_set_bit(7, bitmap) => 1000 0000
73 static unsigned long __find_rev_next_bit(const unsigned long *addr
,
74 unsigned long size
, unsigned long offset
)
76 const unsigned long *p
= addr
+ BIT_WORD(offset
);
77 unsigned long result
= offset
& ~(BITS_PER_LONG
- 1);
79 unsigned long mask
, submask
;
80 unsigned long quot
, rest
;
86 offset
%= BITS_PER_LONG
;
91 quot
= (offset
>> 3) << 3;
94 submask
= (unsigned char)(0xff << rest
) >> rest
;
98 if (size
< BITS_PER_LONG
)
103 size
-= BITS_PER_LONG
;
104 result
+= BITS_PER_LONG
;
106 while (size
& ~(BITS_PER_LONG
-1)) {
110 result
+= BITS_PER_LONG
;
111 size
-= BITS_PER_LONG
;
117 tmp
&= (~0UL >> (BITS_PER_LONG
- size
));
118 if (tmp
== 0UL) /* Are any bits set? */
119 return result
+ size
; /* Nope. */
121 return result
+ __reverse_ffs(tmp
);
124 static unsigned long __find_rev_next_zero_bit(const unsigned long *addr
,
125 unsigned long size
, unsigned long offset
)
127 const unsigned long *p
= addr
+ BIT_WORD(offset
);
128 unsigned long result
= offset
& ~(BITS_PER_LONG
- 1);
130 unsigned long mask
, submask
;
131 unsigned long quot
, rest
;
137 offset
%= BITS_PER_LONG
;
142 quot
= (offset
>> 3) << 3;
144 mask
= ~(~0UL << quot
);
145 submask
= (unsigned char)~((unsigned char)(0xff << rest
) >> rest
);
149 if (size
< BITS_PER_LONG
)
154 size
-= BITS_PER_LONG
;
155 result
+= BITS_PER_LONG
;
157 while (size
& ~(BITS_PER_LONG
- 1)) {
161 result
+= BITS_PER_LONG
;
162 size
-= BITS_PER_LONG
;
170 if (tmp
== ~0UL) /* Are any bits zero? */
171 return result
+ size
; /* Nope. */
173 return result
+ __reverse_ffz(tmp
);
177 * This function balances dirty node and dentry pages.
178 * In addition, it controls garbage collection.
180 void f2fs_balance_fs(struct f2fs_sb_info
*sbi
)
183 * We should do GC or end up with checkpoint, if there are so many dirty
184 * dir/node pages without enough free segments.
186 if (has_not_enough_free_secs(sbi
, 0)) {
187 mutex_lock(&sbi
->gc_mutex
);
192 void f2fs_balance_fs_bg(struct f2fs_sb_info
*sbi
)
194 /* check the # of cached NAT entries and prefree segments */
195 if (try_to_free_nats(sbi
, NAT_ENTRY_PER_BLOCK
) ||
196 excess_prefree_segs(sbi
))
197 f2fs_sync_fs(sbi
->sb
, true);
200 static int issue_flush_thread(void *data
)
202 struct f2fs_sb_info
*sbi
= data
;
203 struct f2fs_sm_info
*sm_i
= SM_I(sbi
);
204 wait_queue_head_t
*q
= &sm_i
->flush_wait_queue
;
206 if (kthread_should_stop())
209 spin_lock(&sm_i
->issue_lock
);
210 if (sm_i
->issue_list
) {
211 sm_i
->dispatch_list
= sm_i
->issue_list
;
212 sm_i
->issue_list
= sm_i
->issue_tail
= NULL
;
214 spin_unlock(&sm_i
->issue_lock
);
216 if (sm_i
->dispatch_list
) {
217 struct bio
*bio
= bio_alloc(GFP_NOIO
, 0);
218 struct flush_cmd
*cmd
, *next
;
221 bio
->bi_bdev
= sbi
->sb
->s_bdev
;
222 ret
= submit_bio_wait(WRITE_FLUSH
, bio
);
224 for (cmd
= sm_i
->dispatch_list
; cmd
; cmd
= next
) {
227 complete(&cmd
->wait
);
229 sm_i
->dispatch_list
= NULL
;
232 wait_event_interruptible(*q
, kthread_should_stop() || sm_i
->issue_list
);
236 int f2fs_issue_flush(struct f2fs_sb_info
*sbi
)
238 struct f2fs_sm_info
*sm_i
= SM_I(sbi
);
239 struct flush_cmd
*cmd
;
242 if (!test_opt(sbi
, FLUSH_MERGE
))
243 return blkdev_issue_flush(sbi
->sb
->s_bdev
, GFP_KERNEL
, NULL
);
245 cmd
= f2fs_kmem_cache_alloc(flush_cmd_slab
, GFP_ATOMIC
);
248 init_completion(&cmd
->wait
);
250 spin_lock(&sm_i
->issue_lock
);
251 if (sm_i
->issue_list
)
252 sm_i
->issue_tail
->next
= cmd
;
254 sm_i
->issue_list
= cmd
;
255 sm_i
->issue_tail
= cmd
;
256 spin_unlock(&sm_i
->issue_lock
);
258 if (!sm_i
->dispatch_list
)
259 wake_up(&sm_i
->flush_wait_queue
);
261 wait_for_completion(&cmd
->wait
);
263 kmem_cache_free(flush_cmd_slab
, cmd
);
267 static void __locate_dirty_segment(struct f2fs_sb_info
*sbi
, unsigned int segno
,
268 enum dirty_type dirty_type
)
270 struct dirty_seglist_info
*dirty_i
= DIRTY_I(sbi
);
272 /* need not be added */
273 if (IS_CURSEG(sbi
, segno
))
276 if (!test_and_set_bit(segno
, dirty_i
->dirty_segmap
[dirty_type
]))
277 dirty_i
->nr_dirty
[dirty_type
]++;
279 if (dirty_type
== DIRTY
) {
280 struct seg_entry
*sentry
= get_seg_entry(sbi
, segno
);
281 enum dirty_type t
= sentry
->type
;
283 if (!test_and_set_bit(segno
, dirty_i
->dirty_segmap
[t
]))
284 dirty_i
->nr_dirty
[t
]++;
288 static void __remove_dirty_segment(struct f2fs_sb_info
*sbi
, unsigned int segno
,
289 enum dirty_type dirty_type
)
291 struct dirty_seglist_info
*dirty_i
= DIRTY_I(sbi
);
293 if (test_and_clear_bit(segno
, dirty_i
->dirty_segmap
[dirty_type
]))
294 dirty_i
->nr_dirty
[dirty_type
]--;
296 if (dirty_type
== DIRTY
) {
297 struct seg_entry
*sentry
= get_seg_entry(sbi
, segno
);
298 enum dirty_type t
= sentry
->type
;
300 if (test_and_clear_bit(segno
, dirty_i
->dirty_segmap
[t
]))
301 dirty_i
->nr_dirty
[t
]--;
303 if (get_valid_blocks(sbi
, segno
, sbi
->segs_per_sec
) == 0)
304 clear_bit(GET_SECNO(sbi
, segno
),
305 dirty_i
->victim_secmap
);
310 * Should not occur error such as -ENOMEM.
311 * Adding dirty entry into seglist is not critical operation.
312 * If a given segment is one of current working segments, it won't be added.
314 static void locate_dirty_segment(struct f2fs_sb_info
*sbi
, unsigned int segno
)
316 struct dirty_seglist_info
*dirty_i
= DIRTY_I(sbi
);
317 unsigned short valid_blocks
;
319 if (segno
== NULL_SEGNO
|| IS_CURSEG(sbi
, segno
))
322 mutex_lock(&dirty_i
->seglist_lock
);
324 valid_blocks
= get_valid_blocks(sbi
, segno
, 0);
326 if (valid_blocks
== 0) {
327 __locate_dirty_segment(sbi
, segno
, PRE
);
328 __remove_dirty_segment(sbi
, segno
, DIRTY
);
329 } else if (valid_blocks
< sbi
->blocks_per_seg
) {
330 __locate_dirty_segment(sbi
, segno
, DIRTY
);
332 /* Recovery routine with SSR needs this */
333 __remove_dirty_segment(sbi
, segno
, DIRTY
);
336 mutex_unlock(&dirty_i
->seglist_lock
);
339 static void f2fs_issue_discard(struct f2fs_sb_info
*sbi
,
340 block_t blkstart
, block_t blklen
)
342 sector_t start
= SECTOR_FROM_BLOCK(sbi
, blkstart
);
343 sector_t len
= SECTOR_FROM_BLOCK(sbi
, blklen
);
344 blkdev_issue_discard(sbi
->sb
->s_bdev
, start
, len
, GFP_NOFS
, 0);
345 trace_f2fs_issue_discard(sbi
->sb
, blkstart
, blklen
);
348 static void add_discard_addrs(struct f2fs_sb_info
*sbi
,
349 unsigned int segno
, struct seg_entry
*se
)
351 struct list_head
*head
= &SM_I(sbi
)->discard_list
;
352 struct discard_entry
*new;
353 int entries
= SIT_VBLOCK_MAP_SIZE
/ sizeof(unsigned long);
354 int max_blocks
= sbi
->blocks_per_seg
;
355 unsigned long *cur_map
= (unsigned long *)se
->cur_valid_map
;
356 unsigned long *ckpt_map
= (unsigned long *)se
->ckpt_valid_map
;
357 unsigned long dmap
[entries
];
358 unsigned int start
= 0, end
= -1;
361 if (!test_opt(sbi
, DISCARD
))
364 /* zero block will be discarded through the prefree list */
365 if (!se
->valid_blocks
|| se
->valid_blocks
== max_blocks
)
368 /* SIT_VBLOCK_MAP_SIZE should be multiple of sizeof(unsigned long) */
369 for (i
= 0; i
< entries
; i
++)
370 dmap
[i
] = (cur_map
[i
] ^ ckpt_map
[i
]) & ckpt_map
[i
];
372 while (SM_I(sbi
)->nr_discards
<= SM_I(sbi
)->max_discards
) {
373 start
= __find_rev_next_bit(dmap
, max_blocks
, end
+ 1);
374 if (start
>= max_blocks
)
377 end
= __find_rev_next_zero_bit(dmap
, max_blocks
, start
+ 1);
379 new = f2fs_kmem_cache_alloc(discard_entry_slab
, GFP_NOFS
);
380 INIT_LIST_HEAD(&new->list
);
381 new->blkaddr
= START_BLOCK(sbi
, segno
) + start
;
382 new->len
= end
- start
;
384 list_add_tail(&new->list
, head
);
385 SM_I(sbi
)->nr_discards
+= end
- start
;
390 * Should call clear_prefree_segments after checkpoint is done.
392 static void set_prefree_as_free_segments(struct f2fs_sb_info
*sbi
)
394 struct dirty_seglist_info
*dirty_i
= DIRTY_I(sbi
);
395 unsigned int segno
= -1;
396 unsigned int total_segs
= TOTAL_SEGS(sbi
);
398 mutex_lock(&dirty_i
->seglist_lock
);
400 segno
= find_next_bit(dirty_i
->dirty_segmap
[PRE
], total_segs
,
402 if (segno
>= total_segs
)
404 __set_test_and_free(sbi
, segno
);
406 mutex_unlock(&dirty_i
->seglist_lock
);
409 void clear_prefree_segments(struct f2fs_sb_info
*sbi
)
411 struct list_head
*head
= &(SM_I(sbi
)->discard_list
);
412 struct discard_entry
*entry
, *this;
413 struct dirty_seglist_info
*dirty_i
= DIRTY_I(sbi
);
414 unsigned long *prefree_map
= dirty_i
->dirty_segmap
[PRE
];
415 unsigned int total_segs
= TOTAL_SEGS(sbi
);
416 unsigned int start
= 0, end
= -1;
418 mutex_lock(&dirty_i
->seglist_lock
);
422 start
= find_next_bit(prefree_map
, total_segs
, end
+ 1);
423 if (start
>= total_segs
)
425 end
= find_next_zero_bit(prefree_map
, total_segs
, start
+ 1);
427 for (i
= start
; i
< end
; i
++)
428 clear_bit(i
, prefree_map
);
430 dirty_i
->nr_dirty
[PRE
] -= end
- start
;
432 if (!test_opt(sbi
, DISCARD
))
435 f2fs_issue_discard(sbi
, START_BLOCK(sbi
, start
),
436 (end
- start
) << sbi
->log_blocks_per_seg
);
438 mutex_unlock(&dirty_i
->seglist_lock
);
440 /* send small discards */
441 list_for_each_entry_safe(entry
, this, head
, list
) {
442 f2fs_issue_discard(sbi
, entry
->blkaddr
, entry
->len
);
443 list_del(&entry
->list
);
444 SM_I(sbi
)->nr_discards
-= entry
->len
;
445 kmem_cache_free(discard_entry_slab
, entry
);
449 static void __mark_sit_entry_dirty(struct f2fs_sb_info
*sbi
, unsigned int segno
)
451 struct sit_info
*sit_i
= SIT_I(sbi
);
452 if (!__test_and_set_bit(segno
, sit_i
->dirty_sentries_bitmap
))
453 sit_i
->dirty_sentries
++;
456 static void __set_sit_entry_type(struct f2fs_sb_info
*sbi
, int type
,
457 unsigned int segno
, int modified
)
459 struct seg_entry
*se
= get_seg_entry(sbi
, segno
);
462 __mark_sit_entry_dirty(sbi
, segno
);
465 static void update_sit_entry(struct f2fs_sb_info
*sbi
, block_t blkaddr
, int del
)
467 struct seg_entry
*se
;
468 unsigned int segno
, offset
;
469 long int new_vblocks
;
471 segno
= GET_SEGNO(sbi
, blkaddr
);
473 se
= get_seg_entry(sbi
, segno
);
474 new_vblocks
= se
->valid_blocks
+ del
;
475 offset
= GET_BLKOFF_FROM_SEG0(sbi
, blkaddr
);
477 f2fs_bug_on((new_vblocks
>> (sizeof(unsigned short) << 3) ||
478 (new_vblocks
> sbi
->blocks_per_seg
)));
480 se
->valid_blocks
= new_vblocks
;
481 se
->mtime
= get_mtime(sbi
);
482 SIT_I(sbi
)->max_mtime
= se
->mtime
;
484 /* Update valid block bitmap */
486 if (f2fs_set_bit(offset
, se
->cur_valid_map
))
489 if (!f2fs_clear_bit(offset
, se
->cur_valid_map
))
492 if (!f2fs_test_bit(offset
, se
->ckpt_valid_map
))
493 se
->ckpt_valid_blocks
+= del
;
495 __mark_sit_entry_dirty(sbi
, segno
);
497 /* update total number of valid blocks to be written in ckpt area */
498 SIT_I(sbi
)->written_valid_blocks
+= del
;
500 if (sbi
->segs_per_sec
> 1)
501 get_sec_entry(sbi
, segno
)->valid_blocks
+= del
;
504 void refresh_sit_entry(struct f2fs_sb_info
*sbi
, block_t old
, block_t
new)
506 update_sit_entry(sbi
, new, 1);
507 if (GET_SEGNO(sbi
, old
) != NULL_SEGNO
)
508 update_sit_entry(sbi
, old
, -1);
510 locate_dirty_segment(sbi
, GET_SEGNO(sbi
, old
));
511 locate_dirty_segment(sbi
, GET_SEGNO(sbi
, new));
514 void invalidate_blocks(struct f2fs_sb_info
*sbi
, block_t addr
)
516 unsigned int segno
= GET_SEGNO(sbi
, addr
);
517 struct sit_info
*sit_i
= SIT_I(sbi
);
519 f2fs_bug_on(addr
== NULL_ADDR
);
520 if (addr
== NEW_ADDR
)
523 /* add it into sit main buffer */
524 mutex_lock(&sit_i
->sentry_lock
);
526 update_sit_entry(sbi
, addr
, -1);
528 /* add it into dirty seglist */
529 locate_dirty_segment(sbi
, segno
);
531 mutex_unlock(&sit_i
->sentry_lock
);
535 * This function should be resided under the curseg_mutex lock
537 static void __add_sum_entry(struct f2fs_sb_info
*sbi
, int type
,
538 struct f2fs_summary
*sum
)
540 struct curseg_info
*curseg
= CURSEG_I(sbi
, type
);
541 void *addr
= curseg
->sum_blk
;
542 addr
+= curseg
->next_blkoff
* sizeof(struct f2fs_summary
);
543 memcpy(addr
, sum
, sizeof(struct f2fs_summary
));
547 * Calculate the number of current summary pages for writing
549 int npages_for_summary_flush(struct f2fs_sb_info
*sbi
)
551 int valid_sum_count
= 0;
554 for (i
= CURSEG_HOT_DATA
; i
<= CURSEG_COLD_DATA
; i
++) {
555 if (sbi
->ckpt
->alloc_type
[i
] == SSR
)
556 valid_sum_count
+= sbi
->blocks_per_seg
;
558 valid_sum_count
+= curseg_blkoff(sbi
, i
);
561 sum_in_page
= (PAGE_CACHE_SIZE
- 2 * SUM_JOURNAL_SIZE
-
562 SUM_FOOTER_SIZE
) / SUMMARY_SIZE
;
563 if (valid_sum_count
<= sum_in_page
)
565 else if ((valid_sum_count
- sum_in_page
) <=
566 (PAGE_CACHE_SIZE
- SUM_FOOTER_SIZE
) / SUMMARY_SIZE
)
572 * Caller should put this summary page
574 struct page
*get_sum_page(struct f2fs_sb_info
*sbi
, unsigned int segno
)
576 return get_meta_page(sbi
, GET_SUM_BLOCK(sbi
, segno
));
579 static void write_sum_page(struct f2fs_sb_info
*sbi
,
580 struct f2fs_summary_block
*sum_blk
, block_t blk_addr
)
582 struct page
*page
= grab_meta_page(sbi
, blk_addr
);
583 void *kaddr
= page_address(page
);
584 memcpy(kaddr
, sum_blk
, PAGE_CACHE_SIZE
);
585 set_page_dirty(page
);
586 f2fs_put_page(page
, 1);
589 static int is_next_segment_free(struct f2fs_sb_info
*sbi
, int type
)
591 struct curseg_info
*curseg
= CURSEG_I(sbi
, type
);
592 unsigned int segno
= curseg
->segno
+ 1;
593 struct free_segmap_info
*free_i
= FREE_I(sbi
);
595 if (segno
< TOTAL_SEGS(sbi
) && segno
% sbi
->segs_per_sec
)
596 return !test_bit(segno
, free_i
->free_segmap
);
601 * Find a new segment from the free segments bitmap to right order
602 * This function should be returned with success, otherwise BUG
604 static void get_new_segment(struct f2fs_sb_info
*sbi
,
605 unsigned int *newseg
, bool new_sec
, int dir
)
607 struct free_segmap_info
*free_i
= FREE_I(sbi
);
608 unsigned int segno
, secno
, zoneno
;
609 unsigned int total_zones
= TOTAL_SECS(sbi
) / sbi
->secs_per_zone
;
610 unsigned int hint
= *newseg
/ sbi
->segs_per_sec
;
611 unsigned int old_zoneno
= GET_ZONENO_FROM_SEGNO(sbi
, *newseg
);
612 unsigned int left_start
= hint
;
617 write_lock(&free_i
->segmap_lock
);
619 if (!new_sec
&& ((*newseg
+ 1) % sbi
->segs_per_sec
)) {
620 segno
= find_next_zero_bit(free_i
->free_segmap
,
621 TOTAL_SEGS(sbi
), *newseg
+ 1);
622 if (segno
- *newseg
< sbi
->segs_per_sec
-
623 (*newseg
% sbi
->segs_per_sec
))
627 secno
= find_next_zero_bit(free_i
->free_secmap
, TOTAL_SECS(sbi
), hint
);
628 if (secno
>= TOTAL_SECS(sbi
)) {
629 if (dir
== ALLOC_RIGHT
) {
630 secno
= find_next_zero_bit(free_i
->free_secmap
,
632 f2fs_bug_on(secno
>= TOTAL_SECS(sbi
));
635 left_start
= hint
- 1;
641 while (test_bit(left_start
, free_i
->free_secmap
)) {
642 if (left_start
> 0) {
646 left_start
= find_next_zero_bit(free_i
->free_secmap
,
648 f2fs_bug_on(left_start
>= TOTAL_SECS(sbi
));
654 segno
= secno
* sbi
->segs_per_sec
;
655 zoneno
= secno
/ sbi
->secs_per_zone
;
657 /* give up on finding another zone */
660 if (sbi
->secs_per_zone
== 1)
662 if (zoneno
== old_zoneno
)
664 if (dir
== ALLOC_LEFT
) {
665 if (!go_left
&& zoneno
+ 1 >= total_zones
)
667 if (go_left
&& zoneno
== 0)
670 for (i
= 0; i
< NR_CURSEG_TYPE
; i
++)
671 if (CURSEG_I(sbi
, i
)->zone
== zoneno
)
674 if (i
< NR_CURSEG_TYPE
) {
675 /* zone is in user, try another */
677 hint
= zoneno
* sbi
->secs_per_zone
- 1;
678 else if (zoneno
+ 1 >= total_zones
)
681 hint
= (zoneno
+ 1) * sbi
->secs_per_zone
;
683 goto find_other_zone
;
686 /* set it as dirty segment in free segmap */
687 f2fs_bug_on(test_bit(segno
, free_i
->free_segmap
));
688 __set_inuse(sbi
, segno
);
690 write_unlock(&free_i
->segmap_lock
);
693 static void reset_curseg(struct f2fs_sb_info
*sbi
, int type
, int modified
)
695 struct curseg_info
*curseg
= CURSEG_I(sbi
, type
);
696 struct summary_footer
*sum_footer
;
698 curseg
->segno
= curseg
->next_segno
;
699 curseg
->zone
= GET_ZONENO_FROM_SEGNO(sbi
, curseg
->segno
);
700 curseg
->next_blkoff
= 0;
701 curseg
->next_segno
= NULL_SEGNO
;
703 sum_footer
= &(curseg
->sum_blk
->footer
);
704 memset(sum_footer
, 0, sizeof(struct summary_footer
));
705 if (IS_DATASEG(type
))
706 SET_SUM_TYPE(sum_footer
, SUM_TYPE_DATA
);
707 if (IS_NODESEG(type
))
708 SET_SUM_TYPE(sum_footer
, SUM_TYPE_NODE
);
709 __set_sit_entry_type(sbi
, type
, curseg
->segno
, modified
);
713 * Allocate a current working segment.
714 * This function always allocates a free segment in LFS manner.
716 static void new_curseg(struct f2fs_sb_info
*sbi
, int type
, bool new_sec
)
718 struct curseg_info
*curseg
= CURSEG_I(sbi
, type
);
719 unsigned int segno
= curseg
->segno
;
720 int dir
= ALLOC_LEFT
;
722 write_sum_page(sbi
, curseg
->sum_blk
,
723 GET_SUM_BLOCK(sbi
, segno
));
724 if (type
== CURSEG_WARM_DATA
|| type
== CURSEG_COLD_DATA
)
727 if (test_opt(sbi
, NOHEAP
))
730 get_new_segment(sbi
, &segno
, new_sec
, dir
);
731 curseg
->next_segno
= segno
;
732 reset_curseg(sbi
, type
, 1);
733 curseg
->alloc_type
= LFS
;
736 static void __next_free_blkoff(struct f2fs_sb_info
*sbi
,
737 struct curseg_info
*seg
, block_t start
)
739 struct seg_entry
*se
= get_seg_entry(sbi
, seg
->segno
);
740 int entries
= SIT_VBLOCK_MAP_SIZE
/ sizeof(unsigned long);
741 unsigned long target_map
[entries
];
742 unsigned long *ckpt_map
= (unsigned long *)se
->ckpt_valid_map
;
743 unsigned long *cur_map
= (unsigned long *)se
->cur_valid_map
;
746 for (i
= 0; i
< entries
; i
++)
747 target_map
[i
] = ckpt_map
[i
] | cur_map
[i
];
749 pos
= __find_rev_next_zero_bit(target_map
, sbi
->blocks_per_seg
, start
);
751 seg
->next_blkoff
= pos
;
755 * If a segment is written by LFS manner, next block offset is just obtained
756 * by increasing the current block offset. However, if a segment is written by
757 * SSR manner, next block offset obtained by calling __next_free_blkoff
759 static void __refresh_next_blkoff(struct f2fs_sb_info
*sbi
,
760 struct curseg_info
*seg
)
762 if (seg
->alloc_type
== SSR
)
763 __next_free_blkoff(sbi
, seg
, seg
->next_blkoff
+ 1);
769 * This function always allocates a used segment (from dirty seglist) by SSR
770 * manner, so it should recover the existing segment information of valid blocks
772 static void change_curseg(struct f2fs_sb_info
*sbi
, int type
, bool reuse
)
774 struct dirty_seglist_info
*dirty_i
= DIRTY_I(sbi
);
775 struct curseg_info
*curseg
= CURSEG_I(sbi
, type
);
776 unsigned int new_segno
= curseg
->next_segno
;
777 struct f2fs_summary_block
*sum_node
;
778 struct page
*sum_page
;
780 write_sum_page(sbi
, curseg
->sum_blk
,
781 GET_SUM_BLOCK(sbi
, curseg
->segno
));
782 __set_test_and_inuse(sbi
, new_segno
);
784 mutex_lock(&dirty_i
->seglist_lock
);
785 __remove_dirty_segment(sbi
, new_segno
, PRE
);
786 __remove_dirty_segment(sbi
, new_segno
, DIRTY
);
787 mutex_unlock(&dirty_i
->seglist_lock
);
789 reset_curseg(sbi
, type
, 1);
790 curseg
->alloc_type
= SSR
;
791 __next_free_blkoff(sbi
, curseg
, 0);
794 sum_page
= get_sum_page(sbi
, new_segno
);
795 sum_node
= (struct f2fs_summary_block
*)page_address(sum_page
);
796 memcpy(curseg
->sum_blk
, sum_node
, SUM_ENTRY_SIZE
);
797 f2fs_put_page(sum_page
, 1);
801 static int get_ssr_segment(struct f2fs_sb_info
*sbi
, int type
)
803 struct curseg_info
*curseg
= CURSEG_I(sbi
, type
);
804 const struct victim_selection
*v_ops
= DIRTY_I(sbi
)->v_ops
;
806 if (IS_NODESEG(type
) || !has_not_enough_free_secs(sbi
, 0))
807 return v_ops
->get_victim(sbi
,
808 &(curseg
)->next_segno
, BG_GC
, type
, SSR
);
810 /* For data segments, let's do SSR more intensively */
811 for (; type
>= CURSEG_HOT_DATA
; type
--)
812 if (v_ops
->get_victim(sbi
, &(curseg
)->next_segno
,
819 * flush out current segment and replace it with new segment
820 * This function should be returned with success, otherwise BUG
822 static void allocate_segment_by_default(struct f2fs_sb_info
*sbi
,
823 int type
, bool force
)
825 struct curseg_info
*curseg
= CURSEG_I(sbi
, type
);
828 new_curseg(sbi
, type
, true);
829 else if (type
== CURSEG_WARM_NODE
)
830 new_curseg(sbi
, type
, false);
831 else if (curseg
->alloc_type
== LFS
&& is_next_segment_free(sbi
, type
))
832 new_curseg(sbi
, type
, false);
833 else if (need_SSR(sbi
) && get_ssr_segment(sbi
, type
))
834 change_curseg(sbi
, type
, true);
836 new_curseg(sbi
, type
, false);
838 stat_inc_seg_type(sbi
, curseg
);
841 void allocate_new_segments(struct f2fs_sb_info
*sbi
)
843 struct curseg_info
*curseg
;
844 unsigned int old_curseg
;
847 for (i
= CURSEG_HOT_DATA
; i
<= CURSEG_COLD_DATA
; i
++) {
848 curseg
= CURSEG_I(sbi
, i
);
849 old_curseg
= curseg
->segno
;
850 SIT_I(sbi
)->s_ops
->allocate_segment(sbi
, i
, true);
851 locate_dirty_segment(sbi
, old_curseg
);
855 static const struct segment_allocation default_salloc_ops
= {
856 .allocate_segment
= allocate_segment_by_default
,
859 static bool __has_curseg_space(struct f2fs_sb_info
*sbi
, int type
)
861 struct curseg_info
*curseg
= CURSEG_I(sbi
, type
);
862 if (curseg
->next_blkoff
< sbi
->blocks_per_seg
)
867 static int __get_segment_type_2(struct page
*page
, enum page_type p_type
)
870 return CURSEG_HOT_DATA
;
872 return CURSEG_HOT_NODE
;
875 static int __get_segment_type_4(struct page
*page
, enum page_type p_type
)
877 if (p_type
== DATA
) {
878 struct inode
*inode
= page
->mapping
->host
;
880 if (S_ISDIR(inode
->i_mode
))
881 return CURSEG_HOT_DATA
;
883 return CURSEG_COLD_DATA
;
885 if (IS_DNODE(page
) && !is_cold_node(page
))
886 return CURSEG_HOT_NODE
;
888 return CURSEG_COLD_NODE
;
892 static int __get_segment_type_6(struct page
*page
, enum page_type p_type
)
894 if (p_type
== DATA
) {
895 struct inode
*inode
= page
->mapping
->host
;
897 if (S_ISDIR(inode
->i_mode
))
898 return CURSEG_HOT_DATA
;
899 else if (is_cold_data(page
) || file_is_cold(inode
))
900 return CURSEG_COLD_DATA
;
902 return CURSEG_WARM_DATA
;
905 return is_cold_node(page
) ? CURSEG_WARM_NODE
:
908 return CURSEG_COLD_NODE
;
912 static int __get_segment_type(struct page
*page
, enum page_type p_type
)
914 struct f2fs_sb_info
*sbi
= F2FS_SB(page
->mapping
->host
->i_sb
);
915 switch (sbi
->active_logs
) {
917 return __get_segment_type_2(page
, p_type
);
919 return __get_segment_type_4(page
, p_type
);
921 /* NR_CURSEG_TYPE(6) logs by default */
922 f2fs_bug_on(sbi
->active_logs
!= NR_CURSEG_TYPE
);
923 return __get_segment_type_6(page
, p_type
);
926 void allocate_data_block(struct f2fs_sb_info
*sbi
, struct page
*page
,
927 block_t old_blkaddr
, block_t
*new_blkaddr
,
928 struct f2fs_summary
*sum
, int type
)
930 struct sit_info
*sit_i
= SIT_I(sbi
);
931 struct curseg_info
*curseg
;
932 unsigned int old_cursegno
;
934 curseg
= CURSEG_I(sbi
, type
);
936 mutex_lock(&curseg
->curseg_mutex
);
938 *new_blkaddr
= NEXT_FREE_BLKADDR(sbi
, curseg
);
939 old_cursegno
= curseg
->segno
;
942 * __add_sum_entry should be resided under the curseg_mutex
943 * because, this function updates a summary entry in the
944 * current summary block.
946 __add_sum_entry(sbi
, type
, sum
);
948 mutex_lock(&sit_i
->sentry_lock
);
949 __refresh_next_blkoff(sbi
, curseg
);
951 stat_inc_block_count(sbi
, curseg
);
953 if (!__has_curseg_space(sbi
, type
))
954 sit_i
->s_ops
->allocate_segment(sbi
, type
, false);
956 * SIT information should be updated before segment allocation,
957 * since SSR needs latest valid block information.
959 refresh_sit_entry(sbi
, old_blkaddr
, *new_blkaddr
);
960 locate_dirty_segment(sbi
, old_cursegno
);
962 mutex_unlock(&sit_i
->sentry_lock
);
964 if (page
&& IS_NODESEG(type
))
965 fill_node_footer_blkaddr(page
, NEXT_FREE_BLKADDR(sbi
, curseg
));
967 mutex_unlock(&curseg
->curseg_mutex
);
970 static void do_write_page(struct f2fs_sb_info
*sbi
, struct page
*page
,
971 block_t old_blkaddr
, block_t
*new_blkaddr
,
972 struct f2fs_summary
*sum
, struct f2fs_io_info
*fio
)
974 int type
= __get_segment_type(page
, fio
->type
);
976 allocate_data_block(sbi
, page
, old_blkaddr
, new_blkaddr
, sum
, type
);
978 /* writeout dirty page into bdev */
979 f2fs_submit_page_mbio(sbi
, page
, *new_blkaddr
, fio
);
982 void write_meta_page(struct f2fs_sb_info
*sbi
, struct page
*page
)
984 struct f2fs_io_info fio
= {
986 .rw
= WRITE_SYNC
| REQ_META
| REQ_PRIO
989 set_page_writeback(page
);
990 f2fs_submit_page_mbio(sbi
, page
, page
->index
, &fio
);
993 void write_node_page(struct f2fs_sb_info
*sbi
, struct page
*page
,
994 struct f2fs_io_info
*fio
,
995 unsigned int nid
, block_t old_blkaddr
, block_t
*new_blkaddr
)
997 struct f2fs_summary sum
;
998 set_summary(&sum
, nid
, 0, 0);
999 do_write_page(sbi
, page
, old_blkaddr
, new_blkaddr
, &sum
, fio
);
1002 void write_data_page(struct page
*page
, struct dnode_of_data
*dn
,
1003 block_t
*new_blkaddr
, struct f2fs_io_info
*fio
)
1005 struct f2fs_sb_info
*sbi
= F2FS_SB(dn
->inode
->i_sb
);
1006 struct f2fs_summary sum
;
1007 struct node_info ni
;
1009 f2fs_bug_on(dn
->data_blkaddr
== NULL_ADDR
);
1010 get_node_info(sbi
, dn
->nid
, &ni
);
1011 set_summary(&sum
, dn
->nid
, dn
->ofs_in_node
, ni
.version
);
1013 do_write_page(sbi
, page
, dn
->data_blkaddr
, new_blkaddr
, &sum
, fio
);
1016 void rewrite_data_page(struct page
*page
, block_t old_blkaddr
,
1017 struct f2fs_io_info
*fio
)
1019 struct inode
*inode
= page
->mapping
->host
;
1020 struct f2fs_sb_info
*sbi
= F2FS_SB(inode
->i_sb
);
1021 f2fs_submit_page_mbio(sbi
, page
, old_blkaddr
, fio
);
1024 void recover_data_page(struct f2fs_sb_info
*sbi
,
1025 struct page
*page
, struct f2fs_summary
*sum
,
1026 block_t old_blkaddr
, block_t new_blkaddr
)
1028 struct sit_info
*sit_i
= SIT_I(sbi
);
1029 struct curseg_info
*curseg
;
1030 unsigned int segno
, old_cursegno
;
1031 struct seg_entry
*se
;
1034 segno
= GET_SEGNO(sbi
, new_blkaddr
);
1035 se
= get_seg_entry(sbi
, segno
);
1038 if (se
->valid_blocks
== 0 && !IS_CURSEG(sbi
, segno
)) {
1039 if (old_blkaddr
== NULL_ADDR
)
1040 type
= CURSEG_COLD_DATA
;
1042 type
= CURSEG_WARM_DATA
;
1044 curseg
= CURSEG_I(sbi
, type
);
1046 mutex_lock(&curseg
->curseg_mutex
);
1047 mutex_lock(&sit_i
->sentry_lock
);
1049 old_cursegno
= curseg
->segno
;
1051 /* change the current segment */
1052 if (segno
!= curseg
->segno
) {
1053 curseg
->next_segno
= segno
;
1054 change_curseg(sbi
, type
, true);
1057 curseg
->next_blkoff
= GET_BLKOFF_FROM_SEG0(sbi
, new_blkaddr
);
1058 __add_sum_entry(sbi
, type
, sum
);
1060 refresh_sit_entry(sbi
, old_blkaddr
, new_blkaddr
);
1061 locate_dirty_segment(sbi
, old_cursegno
);
1063 mutex_unlock(&sit_i
->sentry_lock
);
1064 mutex_unlock(&curseg
->curseg_mutex
);
1067 void rewrite_node_page(struct f2fs_sb_info
*sbi
,
1068 struct page
*page
, struct f2fs_summary
*sum
,
1069 block_t old_blkaddr
, block_t new_blkaddr
)
1071 struct sit_info
*sit_i
= SIT_I(sbi
);
1072 int type
= CURSEG_WARM_NODE
;
1073 struct curseg_info
*curseg
;
1074 unsigned int segno
, old_cursegno
;
1075 block_t next_blkaddr
= next_blkaddr_of_node(page
);
1076 unsigned int next_segno
= GET_SEGNO(sbi
, next_blkaddr
);
1077 struct f2fs_io_info fio
= {
1082 curseg
= CURSEG_I(sbi
, type
);
1084 mutex_lock(&curseg
->curseg_mutex
);
1085 mutex_lock(&sit_i
->sentry_lock
);
1087 segno
= GET_SEGNO(sbi
, new_blkaddr
);
1088 old_cursegno
= curseg
->segno
;
1090 /* change the current segment */
1091 if (segno
!= curseg
->segno
) {
1092 curseg
->next_segno
= segno
;
1093 change_curseg(sbi
, type
, true);
1095 curseg
->next_blkoff
= GET_BLKOFF_FROM_SEG0(sbi
, new_blkaddr
);
1096 __add_sum_entry(sbi
, type
, sum
);
1098 /* change the current log to the next block addr in advance */
1099 if (next_segno
!= segno
) {
1100 curseg
->next_segno
= next_segno
;
1101 change_curseg(sbi
, type
, true);
1103 curseg
->next_blkoff
= GET_BLKOFF_FROM_SEG0(sbi
, next_blkaddr
);
1105 /* rewrite node page */
1106 set_page_writeback(page
);
1107 f2fs_submit_page_mbio(sbi
, page
, new_blkaddr
, &fio
);
1108 f2fs_submit_merged_bio(sbi
, NODE
, WRITE
);
1109 refresh_sit_entry(sbi
, old_blkaddr
, new_blkaddr
);
1110 locate_dirty_segment(sbi
, old_cursegno
);
1112 mutex_unlock(&sit_i
->sentry_lock
);
1113 mutex_unlock(&curseg
->curseg_mutex
);
1116 static inline bool is_merged_page(struct f2fs_sb_info
*sbi
,
1117 struct page
*page
, enum page_type type
)
1119 enum page_type btype
= PAGE_TYPE_OF_BIO(type
);
1120 struct f2fs_bio_info
*io
= &sbi
->write_io
[btype
];
1121 struct bio_vec
*bvec
;
1124 down_read(&io
->io_rwsem
);
1128 bio_for_each_segment_all(bvec
, io
->bio
, i
) {
1129 if (page
== bvec
->bv_page
) {
1130 up_read(&io
->io_rwsem
);
1136 up_read(&io
->io_rwsem
);
1140 void f2fs_wait_on_page_writeback(struct page
*page
,
1141 enum page_type type
)
1143 struct f2fs_sb_info
*sbi
= F2FS_SB(page
->mapping
->host
->i_sb
);
1144 if (PageWriteback(page
)) {
1145 if (is_merged_page(sbi
, page
, type
))
1146 f2fs_submit_merged_bio(sbi
, type
, WRITE
);
1147 wait_on_page_writeback(page
);
1151 static int read_compacted_summaries(struct f2fs_sb_info
*sbi
)
1153 struct f2fs_checkpoint
*ckpt
= F2FS_CKPT(sbi
);
1154 struct curseg_info
*seg_i
;
1155 unsigned char *kaddr
;
1160 start
= start_sum_block(sbi
);
1162 page
= get_meta_page(sbi
, start
++);
1163 kaddr
= (unsigned char *)page_address(page
);
1165 /* Step 1: restore nat cache */
1166 seg_i
= CURSEG_I(sbi
, CURSEG_HOT_DATA
);
1167 memcpy(&seg_i
->sum_blk
->n_nats
, kaddr
, SUM_JOURNAL_SIZE
);
1169 /* Step 2: restore sit cache */
1170 seg_i
= CURSEG_I(sbi
, CURSEG_COLD_DATA
);
1171 memcpy(&seg_i
->sum_blk
->n_sits
, kaddr
+ SUM_JOURNAL_SIZE
,
1173 offset
= 2 * SUM_JOURNAL_SIZE
;
1175 /* Step 3: restore summary entries */
1176 for (i
= CURSEG_HOT_DATA
; i
<= CURSEG_COLD_DATA
; i
++) {
1177 unsigned short blk_off
;
1180 seg_i
= CURSEG_I(sbi
, i
);
1181 segno
= le32_to_cpu(ckpt
->cur_data_segno
[i
]);
1182 blk_off
= le16_to_cpu(ckpt
->cur_data_blkoff
[i
]);
1183 seg_i
->next_segno
= segno
;
1184 reset_curseg(sbi
, i
, 0);
1185 seg_i
->alloc_type
= ckpt
->alloc_type
[i
];
1186 seg_i
->next_blkoff
= blk_off
;
1188 if (seg_i
->alloc_type
== SSR
)
1189 blk_off
= sbi
->blocks_per_seg
;
1191 for (j
= 0; j
< blk_off
; j
++) {
1192 struct f2fs_summary
*s
;
1193 s
= (struct f2fs_summary
*)(kaddr
+ offset
);
1194 seg_i
->sum_blk
->entries
[j
] = *s
;
1195 offset
+= SUMMARY_SIZE
;
1196 if (offset
+ SUMMARY_SIZE
<= PAGE_CACHE_SIZE
-
1200 f2fs_put_page(page
, 1);
1203 page
= get_meta_page(sbi
, start
++);
1204 kaddr
= (unsigned char *)page_address(page
);
1208 f2fs_put_page(page
, 1);
1212 static int read_normal_summaries(struct f2fs_sb_info
*sbi
, int type
)
1214 struct f2fs_checkpoint
*ckpt
= F2FS_CKPT(sbi
);
1215 struct f2fs_summary_block
*sum
;
1216 struct curseg_info
*curseg
;
1218 unsigned short blk_off
;
1219 unsigned int segno
= 0;
1220 block_t blk_addr
= 0;
1222 /* get segment number and block addr */
1223 if (IS_DATASEG(type
)) {
1224 segno
= le32_to_cpu(ckpt
->cur_data_segno
[type
]);
1225 blk_off
= le16_to_cpu(ckpt
->cur_data_blkoff
[type
-
1227 if (is_set_ckpt_flags(ckpt
, CP_UMOUNT_FLAG
))
1228 blk_addr
= sum_blk_addr(sbi
, NR_CURSEG_TYPE
, type
);
1230 blk_addr
= sum_blk_addr(sbi
, NR_CURSEG_DATA_TYPE
, type
);
1232 segno
= le32_to_cpu(ckpt
->cur_node_segno
[type
-
1234 blk_off
= le16_to_cpu(ckpt
->cur_node_blkoff
[type
-
1236 if (is_set_ckpt_flags(ckpt
, CP_UMOUNT_FLAG
))
1237 blk_addr
= sum_blk_addr(sbi
, NR_CURSEG_NODE_TYPE
,
1238 type
- CURSEG_HOT_NODE
);
1240 blk_addr
= GET_SUM_BLOCK(sbi
, segno
);
1243 new = get_meta_page(sbi
, blk_addr
);
1244 sum
= (struct f2fs_summary_block
*)page_address(new);
1246 if (IS_NODESEG(type
)) {
1247 if (is_set_ckpt_flags(ckpt
, CP_UMOUNT_FLAG
)) {
1248 struct f2fs_summary
*ns
= &sum
->entries
[0];
1250 for (i
= 0; i
< sbi
->blocks_per_seg
; i
++, ns
++) {
1252 ns
->ofs_in_node
= 0;
1257 err
= restore_node_summary(sbi
, segno
, sum
);
1259 f2fs_put_page(new, 1);
1265 /* set uncompleted segment to curseg */
1266 curseg
= CURSEG_I(sbi
, type
);
1267 mutex_lock(&curseg
->curseg_mutex
);
1268 memcpy(curseg
->sum_blk
, sum
, PAGE_CACHE_SIZE
);
1269 curseg
->next_segno
= segno
;
1270 reset_curseg(sbi
, type
, 0);
1271 curseg
->alloc_type
= ckpt
->alloc_type
[type
];
1272 curseg
->next_blkoff
= blk_off
;
1273 mutex_unlock(&curseg
->curseg_mutex
);
1274 f2fs_put_page(new, 1);
1278 static int restore_curseg_summaries(struct f2fs_sb_info
*sbi
)
1280 int type
= CURSEG_HOT_DATA
;
1283 if (is_set_ckpt_flags(F2FS_CKPT(sbi
), CP_COMPACT_SUM_FLAG
)) {
1284 /* restore for compacted data summary */
1285 if (read_compacted_summaries(sbi
))
1287 type
= CURSEG_HOT_NODE
;
1290 for (; type
<= CURSEG_COLD_NODE
; type
++) {
1291 err
= read_normal_summaries(sbi
, type
);
1299 static void write_compacted_summaries(struct f2fs_sb_info
*sbi
, block_t blkaddr
)
1302 unsigned char *kaddr
;
1303 struct f2fs_summary
*summary
;
1304 struct curseg_info
*seg_i
;
1305 int written_size
= 0;
1308 page
= grab_meta_page(sbi
, blkaddr
++);
1309 kaddr
= (unsigned char *)page_address(page
);
1311 /* Step 1: write nat cache */
1312 seg_i
= CURSEG_I(sbi
, CURSEG_HOT_DATA
);
1313 memcpy(kaddr
, &seg_i
->sum_blk
->n_nats
, SUM_JOURNAL_SIZE
);
1314 written_size
+= SUM_JOURNAL_SIZE
;
1316 /* Step 2: write sit cache */
1317 seg_i
= CURSEG_I(sbi
, CURSEG_COLD_DATA
);
1318 memcpy(kaddr
+ written_size
, &seg_i
->sum_blk
->n_sits
,
1320 written_size
+= SUM_JOURNAL_SIZE
;
1322 /* Step 3: write summary entries */
1323 for (i
= CURSEG_HOT_DATA
; i
<= CURSEG_COLD_DATA
; i
++) {
1324 unsigned short blkoff
;
1325 seg_i
= CURSEG_I(sbi
, i
);
1326 if (sbi
->ckpt
->alloc_type
[i
] == SSR
)
1327 blkoff
= sbi
->blocks_per_seg
;
1329 blkoff
= curseg_blkoff(sbi
, i
);
1331 for (j
= 0; j
< blkoff
; j
++) {
1333 page
= grab_meta_page(sbi
, blkaddr
++);
1334 kaddr
= (unsigned char *)page_address(page
);
1337 summary
= (struct f2fs_summary
*)(kaddr
+ written_size
);
1338 *summary
= seg_i
->sum_blk
->entries
[j
];
1339 written_size
+= SUMMARY_SIZE
;
1341 if (written_size
+ SUMMARY_SIZE
<= PAGE_CACHE_SIZE
-
1345 set_page_dirty(page
);
1346 f2fs_put_page(page
, 1);
1351 set_page_dirty(page
);
1352 f2fs_put_page(page
, 1);
1356 static void write_normal_summaries(struct f2fs_sb_info
*sbi
,
1357 block_t blkaddr
, int type
)
1360 if (IS_DATASEG(type
))
1361 end
= type
+ NR_CURSEG_DATA_TYPE
;
1363 end
= type
+ NR_CURSEG_NODE_TYPE
;
1365 for (i
= type
; i
< end
; i
++) {
1366 struct curseg_info
*sum
= CURSEG_I(sbi
, i
);
1367 mutex_lock(&sum
->curseg_mutex
);
1368 write_sum_page(sbi
, sum
->sum_blk
, blkaddr
+ (i
- type
));
1369 mutex_unlock(&sum
->curseg_mutex
);
1373 void write_data_summaries(struct f2fs_sb_info
*sbi
, block_t start_blk
)
1375 if (is_set_ckpt_flags(F2FS_CKPT(sbi
), CP_COMPACT_SUM_FLAG
))
1376 write_compacted_summaries(sbi
, start_blk
);
1378 write_normal_summaries(sbi
, start_blk
, CURSEG_HOT_DATA
);
1381 void write_node_summaries(struct f2fs_sb_info
*sbi
, block_t start_blk
)
1383 if (is_set_ckpt_flags(F2FS_CKPT(sbi
), CP_UMOUNT_FLAG
))
1384 write_normal_summaries(sbi
, start_blk
, CURSEG_HOT_NODE
);
1387 int lookup_journal_in_cursum(struct f2fs_summary_block
*sum
, int type
,
1388 unsigned int val
, int alloc
)
1392 if (type
== NAT_JOURNAL
) {
1393 for (i
= 0; i
< nats_in_cursum(sum
); i
++) {
1394 if (le32_to_cpu(nid_in_journal(sum
, i
)) == val
)
1397 if (alloc
&& nats_in_cursum(sum
) < NAT_JOURNAL_ENTRIES
)
1398 return update_nats_in_cursum(sum
, 1);
1399 } else if (type
== SIT_JOURNAL
) {
1400 for (i
= 0; i
< sits_in_cursum(sum
); i
++)
1401 if (le32_to_cpu(segno_in_journal(sum
, i
)) == val
)
1403 if (alloc
&& sits_in_cursum(sum
) < SIT_JOURNAL_ENTRIES
)
1404 return update_sits_in_cursum(sum
, 1);
1409 static struct page
*get_current_sit_page(struct f2fs_sb_info
*sbi
,
1412 struct sit_info
*sit_i
= SIT_I(sbi
);
1413 unsigned int offset
= SIT_BLOCK_OFFSET(sit_i
, segno
);
1414 block_t blk_addr
= sit_i
->sit_base_addr
+ offset
;
1416 check_seg_range(sbi
, segno
);
1418 /* calculate sit block address */
1419 if (f2fs_test_bit(offset
, sit_i
->sit_bitmap
))
1420 blk_addr
+= sit_i
->sit_blocks
;
1422 return get_meta_page(sbi
, blk_addr
);
1425 static struct page
*get_next_sit_page(struct f2fs_sb_info
*sbi
,
1428 struct sit_info
*sit_i
= SIT_I(sbi
);
1429 struct page
*src_page
, *dst_page
;
1430 pgoff_t src_off
, dst_off
;
1431 void *src_addr
, *dst_addr
;
1433 src_off
= current_sit_addr(sbi
, start
);
1434 dst_off
= next_sit_addr(sbi
, src_off
);
1436 /* get current sit block page without lock */
1437 src_page
= get_meta_page(sbi
, src_off
);
1438 dst_page
= grab_meta_page(sbi
, dst_off
);
1439 f2fs_bug_on(PageDirty(src_page
));
1441 src_addr
= page_address(src_page
);
1442 dst_addr
= page_address(dst_page
);
1443 memcpy(dst_addr
, src_addr
, PAGE_CACHE_SIZE
);
1445 set_page_dirty(dst_page
);
1446 f2fs_put_page(src_page
, 1);
1448 set_to_next_sit(sit_i
, start
);
1453 static bool flush_sits_in_journal(struct f2fs_sb_info
*sbi
)
1455 struct curseg_info
*curseg
= CURSEG_I(sbi
, CURSEG_COLD_DATA
);
1456 struct f2fs_summary_block
*sum
= curseg
->sum_blk
;
1460 * If the journal area in the current summary is full of sit entries,
1461 * all the sit entries will be flushed. Otherwise the sit entries
1462 * are not able to replace with newly hot sit entries.
1464 if (sits_in_cursum(sum
) >= SIT_JOURNAL_ENTRIES
) {
1465 for (i
= sits_in_cursum(sum
) - 1; i
>= 0; i
--) {
1467 segno
= le32_to_cpu(segno_in_journal(sum
, i
));
1468 __mark_sit_entry_dirty(sbi
, segno
);
1470 update_sits_in_cursum(sum
, -sits_in_cursum(sum
));
1477 * CP calls this function, which flushes SIT entries including sit_journal,
1478 * and moves prefree segs to free segs.
1480 void flush_sit_entries(struct f2fs_sb_info
*sbi
)
1482 struct sit_info
*sit_i
= SIT_I(sbi
);
1483 unsigned long *bitmap
= sit_i
->dirty_sentries_bitmap
;
1484 struct curseg_info
*curseg
= CURSEG_I(sbi
, CURSEG_COLD_DATA
);
1485 struct f2fs_summary_block
*sum
= curseg
->sum_blk
;
1486 unsigned long nsegs
= TOTAL_SEGS(sbi
);
1487 struct page
*page
= NULL
;
1488 struct f2fs_sit_block
*raw_sit
= NULL
;
1489 unsigned int start
= 0, end
= 0;
1490 unsigned int segno
= -1;
1493 mutex_lock(&curseg
->curseg_mutex
);
1494 mutex_lock(&sit_i
->sentry_lock
);
1497 * "flushed" indicates whether sit entries in journal are flushed
1498 * to the SIT area or not.
1500 flushed
= flush_sits_in_journal(sbi
);
1502 while ((segno
= find_next_bit(bitmap
, nsegs
, segno
+ 1)) < nsegs
) {
1503 struct seg_entry
*se
= get_seg_entry(sbi
, segno
);
1504 int sit_offset
, offset
;
1506 sit_offset
= SIT_ENTRY_OFFSET(sit_i
, segno
);
1508 /* add discard candidates */
1509 if (SM_I(sbi
)->nr_discards
< SM_I(sbi
)->max_discards
)
1510 add_discard_addrs(sbi
, segno
, se
);
1515 offset
= lookup_journal_in_cursum(sum
, SIT_JOURNAL
, segno
, 1);
1517 segno_in_journal(sum
, offset
) = cpu_to_le32(segno
);
1518 seg_info_to_raw_sit(se
, &sit_in_journal(sum
, offset
));
1522 if (!page
|| (start
> segno
) || (segno
> end
)) {
1524 f2fs_put_page(page
, 1);
1528 start
= START_SEGNO(sit_i
, segno
);
1529 end
= start
+ SIT_ENTRY_PER_BLOCK
- 1;
1531 /* read sit block that will be updated */
1532 page
= get_next_sit_page(sbi
, start
);
1533 raw_sit
= page_address(page
);
1536 /* udpate entry in SIT block */
1537 seg_info_to_raw_sit(se
, &raw_sit
->entries
[sit_offset
]);
1539 __clear_bit(segno
, bitmap
);
1540 sit_i
->dirty_sentries
--;
1542 mutex_unlock(&sit_i
->sentry_lock
);
1543 mutex_unlock(&curseg
->curseg_mutex
);
1545 /* writeout last modified SIT block */
1546 f2fs_put_page(page
, 1);
1548 set_prefree_as_free_segments(sbi
);
1551 static int build_sit_info(struct f2fs_sb_info
*sbi
)
1553 struct f2fs_super_block
*raw_super
= F2FS_RAW_SUPER(sbi
);
1554 struct f2fs_checkpoint
*ckpt
= F2FS_CKPT(sbi
);
1555 struct sit_info
*sit_i
;
1556 unsigned int sit_segs
, start
;
1557 char *src_bitmap
, *dst_bitmap
;
1558 unsigned int bitmap_size
;
1560 /* allocate memory for SIT information */
1561 sit_i
= kzalloc(sizeof(struct sit_info
), GFP_KERNEL
);
1565 SM_I(sbi
)->sit_info
= sit_i
;
1567 sit_i
->sentries
= vzalloc(TOTAL_SEGS(sbi
) * sizeof(struct seg_entry
));
1568 if (!sit_i
->sentries
)
1571 bitmap_size
= f2fs_bitmap_size(TOTAL_SEGS(sbi
));
1572 sit_i
->dirty_sentries_bitmap
= kzalloc(bitmap_size
, GFP_KERNEL
);
1573 if (!sit_i
->dirty_sentries_bitmap
)
1576 for (start
= 0; start
< TOTAL_SEGS(sbi
); start
++) {
1577 sit_i
->sentries
[start
].cur_valid_map
1578 = kzalloc(SIT_VBLOCK_MAP_SIZE
, GFP_KERNEL
);
1579 sit_i
->sentries
[start
].ckpt_valid_map
1580 = kzalloc(SIT_VBLOCK_MAP_SIZE
, GFP_KERNEL
);
1581 if (!sit_i
->sentries
[start
].cur_valid_map
1582 || !sit_i
->sentries
[start
].ckpt_valid_map
)
1586 if (sbi
->segs_per_sec
> 1) {
1587 sit_i
->sec_entries
= vzalloc(TOTAL_SECS(sbi
) *
1588 sizeof(struct sec_entry
));
1589 if (!sit_i
->sec_entries
)
1593 /* get information related with SIT */
1594 sit_segs
= le32_to_cpu(raw_super
->segment_count_sit
) >> 1;
1596 /* setup SIT bitmap from ckeckpoint pack */
1597 bitmap_size
= __bitmap_size(sbi
, SIT_BITMAP
);
1598 src_bitmap
= __bitmap_ptr(sbi
, SIT_BITMAP
);
1600 dst_bitmap
= kmemdup(src_bitmap
, bitmap_size
, GFP_KERNEL
);
1604 /* init SIT information */
1605 sit_i
->s_ops
= &default_salloc_ops
;
1607 sit_i
->sit_base_addr
= le32_to_cpu(raw_super
->sit_blkaddr
);
1608 sit_i
->sit_blocks
= sit_segs
<< sbi
->log_blocks_per_seg
;
1609 sit_i
->written_valid_blocks
= le64_to_cpu(ckpt
->valid_block_count
);
1610 sit_i
->sit_bitmap
= dst_bitmap
;
1611 sit_i
->bitmap_size
= bitmap_size
;
1612 sit_i
->dirty_sentries
= 0;
1613 sit_i
->sents_per_block
= SIT_ENTRY_PER_BLOCK
;
1614 sit_i
->elapsed_time
= le64_to_cpu(sbi
->ckpt
->elapsed_time
);
1615 sit_i
->mounted_time
= CURRENT_TIME_SEC
.tv_sec
;
1616 mutex_init(&sit_i
->sentry_lock
);
1620 static int build_free_segmap(struct f2fs_sb_info
*sbi
)
1622 struct f2fs_sm_info
*sm_info
= SM_I(sbi
);
1623 struct free_segmap_info
*free_i
;
1624 unsigned int bitmap_size
, sec_bitmap_size
;
1626 /* allocate memory for free segmap information */
1627 free_i
= kzalloc(sizeof(struct free_segmap_info
), GFP_KERNEL
);
1631 SM_I(sbi
)->free_info
= free_i
;
1633 bitmap_size
= f2fs_bitmap_size(TOTAL_SEGS(sbi
));
1634 free_i
->free_segmap
= kmalloc(bitmap_size
, GFP_KERNEL
);
1635 if (!free_i
->free_segmap
)
1638 sec_bitmap_size
= f2fs_bitmap_size(TOTAL_SECS(sbi
));
1639 free_i
->free_secmap
= kmalloc(sec_bitmap_size
, GFP_KERNEL
);
1640 if (!free_i
->free_secmap
)
1643 /* set all segments as dirty temporarily */
1644 memset(free_i
->free_segmap
, 0xff, bitmap_size
);
1645 memset(free_i
->free_secmap
, 0xff, sec_bitmap_size
);
1647 /* init free segmap information */
1648 free_i
->start_segno
=
1649 (unsigned int) GET_SEGNO_FROM_SEG0(sbi
, sm_info
->main_blkaddr
);
1650 free_i
->free_segments
= 0;
1651 free_i
->free_sections
= 0;
1652 rwlock_init(&free_i
->segmap_lock
);
1656 static int build_curseg(struct f2fs_sb_info
*sbi
)
1658 struct curseg_info
*array
;
1661 array
= kzalloc(sizeof(*array
) * NR_CURSEG_TYPE
, GFP_KERNEL
);
1665 SM_I(sbi
)->curseg_array
= array
;
1667 for (i
= 0; i
< NR_CURSEG_TYPE
; i
++) {
1668 mutex_init(&array
[i
].curseg_mutex
);
1669 array
[i
].sum_blk
= kzalloc(PAGE_CACHE_SIZE
, GFP_KERNEL
);
1670 if (!array
[i
].sum_blk
)
1672 array
[i
].segno
= NULL_SEGNO
;
1673 array
[i
].next_blkoff
= 0;
1675 return restore_curseg_summaries(sbi
);
1678 static void build_sit_entries(struct f2fs_sb_info
*sbi
)
1680 struct sit_info
*sit_i
= SIT_I(sbi
);
1681 struct curseg_info
*curseg
= CURSEG_I(sbi
, CURSEG_COLD_DATA
);
1682 struct f2fs_summary_block
*sum
= curseg
->sum_blk
;
1683 int sit_blk_cnt
= SIT_BLK_CNT(sbi
);
1684 unsigned int i
, start
, end
;
1685 unsigned int readed
, start_blk
= 0;
1686 int nrpages
= MAX_BIO_BLOCKS(max_hw_blocks(sbi
));
1689 readed
= ra_meta_pages(sbi
, start_blk
, nrpages
, META_SIT
);
1691 start
= start_blk
* sit_i
->sents_per_block
;
1692 end
= (start_blk
+ readed
) * sit_i
->sents_per_block
;
1694 for (; start
< end
&& start
< TOTAL_SEGS(sbi
); start
++) {
1695 struct seg_entry
*se
= &sit_i
->sentries
[start
];
1696 struct f2fs_sit_block
*sit_blk
;
1697 struct f2fs_sit_entry sit
;
1700 mutex_lock(&curseg
->curseg_mutex
);
1701 for (i
= 0; i
< sits_in_cursum(sum
); i
++) {
1702 if (le32_to_cpu(segno_in_journal(sum
, i
))
1704 sit
= sit_in_journal(sum
, i
);
1705 mutex_unlock(&curseg
->curseg_mutex
);
1709 mutex_unlock(&curseg
->curseg_mutex
);
1711 page
= get_current_sit_page(sbi
, start
);
1712 sit_blk
= (struct f2fs_sit_block
*)page_address(page
);
1713 sit
= sit_blk
->entries
[SIT_ENTRY_OFFSET(sit_i
, start
)];
1714 f2fs_put_page(page
, 1);
1716 check_block_count(sbi
, start
, &sit
);
1717 seg_info_from_raw_sit(se
, &sit
);
1718 if (sbi
->segs_per_sec
> 1) {
1719 struct sec_entry
*e
= get_sec_entry(sbi
, start
);
1720 e
->valid_blocks
+= se
->valid_blocks
;
1723 start_blk
+= readed
;
1724 } while (start_blk
< sit_blk_cnt
);
1727 static void init_free_segmap(struct f2fs_sb_info
*sbi
)
1732 for (start
= 0; start
< TOTAL_SEGS(sbi
); start
++) {
1733 struct seg_entry
*sentry
= get_seg_entry(sbi
, start
);
1734 if (!sentry
->valid_blocks
)
1735 __set_free(sbi
, start
);
1738 /* set use the current segments */
1739 for (type
= CURSEG_HOT_DATA
; type
<= CURSEG_COLD_NODE
; type
++) {
1740 struct curseg_info
*curseg_t
= CURSEG_I(sbi
, type
);
1741 __set_test_and_inuse(sbi
, curseg_t
->segno
);
1745 static void init_dirty_segmap(struct f2fs_sb_info
*sbi
)
1747 struct dirty_seglist_info
*dirty_i
= DIRTY_I(sbi
);
1748 struct free_segmap_info
*free_i
= FREE_I(sbi
);
1749 unsigned int segno
= 0, offset
= 0, total_segs
= TOTAL_SEGS(sbi
);
1750 unsigned short valid_blocks
;
1753 /* find dirty segment based on free segmap */
1754 segno
= find_next_inuse(free_i
, total_segs
, offset
);
1755 if (segno
>= total_segs
)
1758 valid_blocks
= get_valid_blocks(sbi
, segno
, 0);
1759 if (valid_blocks
>= sbi
->blocks_per_seg
|| !valid_blocks
)
1761 mutex_lock(&dirty_i
->seglist_lock
);
1762 __locate_dirty_segment(sbi
, segno
, DIRTY
);
1763 mutex_unlock(&dirty_i
->seglist_lock
);
1767 static int init_victim_secmap(struct f2fs_sb_info
*sbi
)
1769 struct dirty_seglist_info
*dirty_i
= DIRTY_I(sbi
);
1770 unsigned int bitmap_size
= f2fs_bitmap_size(TOTAL_SECS(sbi
));
1772 dirty_i
->victim_secmap
= kzalloc(bitmap_size
, GFP_KERNEL
);
1773 if (!dirty_i
->victim_secmap
)
1778 static int build_dirty_segmap(struct f2fs_sb_info
*sbi
)
1780 struct dirty_seglist_info
*dirty_i
;
1781 unsigned int bitmap_size
, i
;
1783 /* allocate memory for dirty segments list information */
1784 dirty_i
= kzalloc(sizeof(struct dirty_seglist_info
), GFP_KERNEL
);
1788 SM_I(sbi
)->dirty_info
= dirty_i
;
1789 mutex_init(&dirty_i
->seglist_lock
);
1791 bitmap_size
= f2fs_bitmap_size(TOTAL_SEGS(sbi
));
1793 for (i
= 0; i
< NR_DIRTY_TYPE
; i
++) {
1794 dirty_i
->dirty_segmap
[i
] = kzalloc(bitmap_size
, GFP_KERNEL
);
1795 if (!dirty_i
->dirty_segmap
[i
])
1799 init_dirty_segmap(sbi
);
1800 return init_victim_secmap(sbi
);
1804 * Update min, max modified time for cost-benefit GC algorithm
1806 static void init_min_max_mtime(struct f2fs_sb_info
*sbi
)
1808 struct sit_info
*sit_i
= SIT_I(sbi
);
1811 mutex_lock(&sit_i
->sentry_lock
);
1813 sit_i
->min_mtime
= LLONG_MAX
;
1815 for (segno
= 0; segno
< TOTAL_SEGS(sbi
); segno
+= sbi
->segs_per_sec
) {
1817 unsigned long long mtime
= 0;
1819 for (i
= 0; i
< sbi
->segs_per_sec
; i
++)
1820 mtime
+= get_seg_entry(sbi
, segno
+ i
)->mtime
;
1822 mtime
= div_u64(mtime
, sbi
->segs_per_sec
);
1824 if (sit_i
->min_mtime
> mtime
)
1825 sit_i
->min_mtime
= mtime
;
1827 sit_i
->max_mtime
= get_mtime(sbi
);
1828 mutex_unlock(&sit_i
->sentry_lock
);
1831 int build_segment_manager(struct f2fs_sb_info
*sbi
)
1833 struct f2fs_super_block
*raw_super
= F2FS_RAW_SUPER(sbi
);
1834 struct f2fs_checkpoint
*ckpt
= F2FS_CKPT(sbi
);
1835 dev_t dev
= sbi
->sb
->s_bdev
->bd_dev
;
1836 struct f2fs_sm_info
*sm_info
;
1839 sm_info
= kzalloc(sizeof(struct f2fs_sm_info
), GFP_KERNEL
);
1844 sbi
->sm_info
= sm_info
;
1845 INIT_LIST_HEAD(&sm_info
->wblist_head
);
1846 spin_lock_init(&sm_info
->wblist_lock
);
1847 sm_info
->seg0_blkaddr
= le32_to_cpu(raw_super
->segment0_blkaddr
);
1848 sm_info
->main_blkaddr
= le32_to_cpu(raw_super
->main_blkaddr
);
1849 sm_info
->segment_count
= le32_to_cpu(raw_super
->segment_count
);
1850 sm_info
->reserved_segments
= le32_to_cpu(ckpt
->rsvd_segment_count
);
1851 sm_info
->ovp_segments
= le32_to_cpu(ckpt
->overprov_segment_count
);
1852 sm_info
->main_segments
= le32_to_cpu(raw_super
->segment_count_main
);
1853 sm_info
->ssa_blkaddr
= le32_to_cpu(raw_super
->ssa_blkaddr
);
1854 sm_info
->rec_prefree_segments
= sm_info
->main_segments
*
1855 DEF_RECLAIM_PREFREE_SEGMENTS
/ 100;
1856 sm_info
->ipu_policy
= F2FS_IPU_DISABLE
;
1857 sm_info
->min_ipu_util
= DEF_MIN_IPU_UTIL
;
1859 INIT_LIST_HEAD(&sm_info
->discard_list
);
1860 sm_info
->nr_discards
= 0;
1861 sm_info
->max_discards
= 0;
1863 if (test_opt(sbi
, FLUSH_MERGE
)) {
1864 spin_lock_init(&sm_info
->issue_lock
);
1865 init_waitqueue_head(&sm_info
->flush_wait_queue
);
1867 sm_info
->f2fs_issue_flush
= kthread_run(issue_flush_thread
, sbi
,
1868 "f2fs_flush-%u:%u", MAJOR(dev
), MINOR(dev
));
1869 if (IS_ERR(sm_info
->f2fs_issue_flush
))
1870 return PTR_ERR(sm_info
->f2fs_issue_flush
);
1873 err
= build_sit_info(sbi
);
1876 err
= build_free_segmap(sbi
);
1879 err
= build_curseg(sbi
);
1883 /* reinit free segmap based on SIT */
1884 build_sit_entries(sbi
);
1886 init_free_segmap(sbi
);
1887 err
= build_dirty_segmap(sbi
);
1891 init_min_max_mtime(sbi
);
1895 static void discard_dirty_segmap(struct f2fs_sb_info
*sbi
,
1896 enum dirty_type dirty_type
)
1898 struct dirty_seglist_info
*dirty_i
= DIRTY_I(sbi
);
1900 mutex_lock(&dirty_i
->seglist_lock
);
1901 kfree(dirty_i
->dirty_segmap
[dirty_type
]);
1902 dirty_i
->nr_dirty
[dirty_type
] = 0;
1903 mutex_unlock(&dirty_i
->seglist_lock
);
1906 static void destroy_victim_secmap(struct f2fs_sb_info
*sbi
)
1908 struct dirty_seglist_info
*dirty_i
= DIRTY_I(sbi
);
1909 kfree(dirty_i
->victim_secmap
);
1912 static void destroy_dirty_segmap(struct f2fs_sb_info
*sbi
)
1914 struct dirty_seglist_info
*dirty_i
= DIRTY_I(sbi
);
1920 /* discard pre-free/dirty segments list */
1921 for (i
= 0; i
< NR_DIRTY_TYPE
; i
++)
1922 discard_dirty_segmap(sbi
, i
);
1924 destroy_victim_secmap(sbi
);
1925 SM_I(sbi
)->dirty_info
= NULL
;
1929 static void destroy_curseg(struct f2fs_sb_info
*sbi
)
1931 struct curseg_info
*array
= SM_I(sbi
)->curseg_array
;
1936 SM_I(sbi
)->curseg_array
= NULL
;
1937 for (i
= 0; i
< NR_CURSEG_TYPE
; i
++)
1938 kfree(array
[i
].sum_blk
);
1942 static void destroy_free_segmap(struct f2fs_sb_info
*sbi
)
1944 struct free_segmap_info
*free_i
= SM_I(sbi
)->free_info
;
1947 SM_I(sbi
)->free_info
= NULL
;
1948 kfree(free_i
->free_segmap
);
1949 kfree(free_i
->free_secmap
);
1953 static void destroy_sit_info(struct f2fs_sb_info
*sbi
)
1955 struct sit_info
*sit_i
= SIT_I(sbi
);
1961 if (sit_i
->sentries
) {
1962 for (start
= 0; start
< TOTAL_SEGS(sbi
); start
++) {
1963 kfree(sit_i
->sentries
[start
].cur_valid_map
);
1964 kfree(sit_i
->sentries
[start
].ckpt_valid_map
);
1967 vfree(sit_i
->sentries
);
1968 vfree(sit_i
->sec_entries
);
1969 kfree(sit_i
->dirty_sentries_bitmap
);
1971 SM_I(sbi
)->sit_info
= NULL
;
1972 kfree(sit_i
->sit_bitmap
);
1976 void destroy_segment_manager(struct f2fs_sb_info
*sbi
)
1978 struct f2fs_sm_info
*sm_info
= SM_I(sbi
);
1981 if (sm_info
->f2fs_issue_flush
)
1982 kthread_stop(sm_info
->f2fs_issue_flush
);
1983 destroy_dirty_segmap(sbi
);
1984 destroy_curseg(sbi
);
1985 destroy_free_segmap(sbi
);
1986 destroy_sit_info(sbi
);
1987 sbi
->sm_info
= NULL
;
1991 int __init
create_segment_manager_caches(void)
1993 discard_entry_slab
= f2fs_kmem_cache_create("discard_entry",
1994 sizeof(struct discard_entry
));
1995 if (!discard_entry_slab
)
1997 flush_cmd_slab
= f2fs_kmem_cache_create("flush_command",
1998 sizeof(struct flush_cmd
));
1999 if (!flush_cmd_slab
) {
2000 kmem_cache_destroy(discard_entry_slab
);
2006 void destroy_segment_manager_caches(void)
2008 kmem_cache_destroy(discard_entry_slab
);
2009 kmem_cache_destroy(flush_cmd_slab
);