blob: c386910dacc53b5300f019eec517fa88a04461bc [file] [log] [blame]
Jaegeuk Kim0a8165d2012-11-29 13:28:09 +09001/*
Jaegeuk Kim7bc09002012-11-02 17:13:01 +09002 * fs/f2fs/gc.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/module.h>
13#include <linux/backing-dev.h>
14#include <linux/proc_fs.h>
15#include <linux/init.h>
16#include <linux/f2fs_fs.h>
17#include <linux/kthread.h>
18#include <linux/delay.h>
19#include <linux/freezer.h>
20#include <linux/blkdev.h>
21
22#include "f2fs.h"
23#include "node.h"
24#include "segment.h"
25#include "gc.h"
26
27static struct kmem_cache *winode_slab;
28
29static int gc_thread_func(void *data)
30{
31 struct f2fs_sb_info *sbi = data;
32 wait_queue_head_t *wq = &sbi->gc_thread->gc_wait_queue_head;
33 long wait_ms;
34
35 wait_ms = GC_THREAD_MIN_SLEEP_TIME;
36
37 do {
38 if (try_to_freeze())
39 continue;
40 else
41 wait_event_interruptible_timeout(*wq,
42 kthread_should_stop(),
43 msecs_to_jiffies(wait_ms));
44 if (kthread_should_stop())
45 break;
46
47 f2fs_balance_fs(sbi);
48
49 if (!test_opt(sbi, BG_GC))
50 continue;
51
52 /*
53 * [GC triggering condition]
54 * 0. GC is not conducted currently.
55 * 1. There are enough dirty segments.
56 * 2. IO subsystem is idle by checking the # of writeback pages.
57 * 3. IO subsystem is idle by checking the # of requests in
58 * bdev's request list.
59 *
60 * Note) We have to avoid triggering GCs too much frequently.
61 * Because it is possible that some segments can be
62 * invalidated soon after by user update or deletion.
63 * So, I'd like to wait some time to collect dirty segments.
64 */
65 if (!mutex_trylock(&sbi->gc_mutex))
66 continue;
67
68 if (!is_idle(sbi)) {
69 wait_ms = increase_sleep_time(wait_ms);
70 mutex_unlock(&sbi->gc_mutex);
71 continue;
72 }
73
74 if (has_enough_invalid_blocks(sbi))
75 wait_ms = decrease_sleep_time(wait_ms);
76 else
77 wait_ms = increase_sleep_time(wait_ms);
78
79 sbi->bg_gc++;
80
Jaegeuk Kim408e9372013-01-03 17:55:52 +090081 if (f2fs_gc(sbi) == GC_NONE)
Jaegeuk Kim7bc09002012-11-02 17:13:01 +090082 wait_ms = GC_THREAD_NOGC_SLEEP_TIME;
83 else if (wait_ms == GC_THREAD_NOGC_SLEEP_TIME)
84 wait_ms = GC_THREAD_MAX_SLEEP_TIME;
85
86 } while (!kthread_should_stop());
87 return 0;
88}
89
90int start_gc_thread(struct f2fs_sb_info *sbi)
91{
Namjae Jeon1042d602012-12-01 10:56:13 +090092 struct f2fs_gc_kthread *gc_th;
Jaegeuk Kim7bc09002012-11-02 17:13:01 +090093
94 gc_th = kmalloc(sizeof(struct f2fs_gc_kthread), GFP_KERNEL);
95 if (!gc_th)
96 return -ENOMEM;
97
98 sbi->gc_thread = gc_th;
99 init_waitqueue_head(&sbi->gc_thread->gc_wait_queue_head);
100 sbi->gc_thread->f2fs_gc_task = kthread_run(gc_thread_func, sbi,
101 GC_THREAD_NAME);
102 if (IS_ERR(gc_th->f2fs_gc_task)) {
103 kfree(gc_th);
104 return -ENOMEM;
105 }
106 return 0;
107}
108
109void stop_gc_thread(struct f2fs_sb_info *sbi)
110{
111 struct f2fs_gc_kthread *gc_th = sbi->gc_thread;
112 if (!gc_th)
113 return;
114 kthread_stop(gc_th->f2fs_gc_task);
115 kfree(gc_th);
116 sbi->gc_thread = NULL;
117}
118
119static int select_gc_type(int gc_type)
120{
121 return (gc_type == BG_GC) ? GC_CB : GC_GREEDY;
122}
123
124static void select_policy(struct f2fs_sb_info *sbi, int gc_type,
125 int type, struct victim_sel_policy *p)
126{
127 struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
128
129 if (p->alloc_mode) {
130 p->gc_mode = GC_GREEDY;
131 p->dirty_segmap = dirty_i->dirty_segmap[type];
132 p->ofs_unit = 1;
133 } else {
134 p->gc_mode = select_gc_type(gc_type);
135 p->dirty_segmap = dirty_i->dirty_segmap[DIRTY];
136 p->ofs_unit = sbi->segs_per_sec;
137 }
138 p->offset = sbi->last_victim[p->gc_mode];
139}
140
141static unsigned int get_max_cost(struct f2fs_sb_info *sbi,
142 struct victim_sel_policy *p)
143{
144 if (p->gc_mode == GC_GREEDY)
145 return (1 << sbi->log_blocks_per_seg) * p->ofs_unit;
146 else if (p->gc_mode == GC_CB)
147 return UINT_MAX;
148 else /* No other gc_mode */
149 return 0;
150}
151
152static unsigned int check_bg_victims(struct f2fs_sb_info *sbi)
153{
154 struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
155 unsigned int segno;
156
157 /*
158 * If the gc_type is FG_GC, we can select victim segments
159 * selected by background GC before.
160 * Those segments guarantee they have small valid blocks.
161 */
162 segno = find_next_bit(dirty_i->victim_segmap[BG_GC],
163 TOTAL_SEGS(sbi), 0);
164 if (segno < TOTAL_SEGS(sbi)) {
165 clear_bit(segno, dirty_i->victim_segmap[BG_GC]);
166 return segno;
167 }
168 return NULL_SEGNO;
169}
170
171static unsigned int get_cb_cost(struct f2fs_sb_info *sbi, unsigned int segno)
172{
173 struct sit_info *sit_i = SIT_I(sbi);
174 unsigned int secno = GET_SECNO(sbi, segno);
175 unsigned int start = secno * sbi->segs_per_sec;
176 unsigned long long mtime = 0;
177 unsigned int vblocks;
178 unsigned char age = 0;
179 unsigned char u;
180 unsigned int i;
181
182 for (i = 0; i < sbi->segs_per_sec; i++)
183 mtime += get_seg_entry(sbi, start + i)->mtime;
184 vblocks = get_valid_blocks(sbi, segno, sbi->segs_per_sec);
185
186 mtime = div_u64(mtime, sbi->segs_per_sec);
187 vblocks = div_u64(vblocks, sbi->segs_per_sec);
188
189 u = (vblocks * 100) >> sbi->log_blocks_per_seg;
190
191 /* Handle if the system time is changed by user */
192 if (mtime < sit_i->min_mtime)
193 sit_i->min_mtime = mtime;
194 if (mtime > sit_i->max_mtime)
195 sit_i->max_mtime = mtime;
196 if (sit_i->max_mtime != sit_i->min_mtime)
197 age = 100 - div64_u64(100 * (mtime - sit_i->min_mtime),
198 sit_i->max_mtime - sit_i->min_mtime);
199
200 return UINT_MAX - ((100 * (100 - u) * age) / (100 + u));
201}
202
203static unsigned int get_gc_cost(struct f2fs_sb_info *sbi, unsigned int segno,
204 struct victim_sel_policy *p)
205{
206 if (p->alloc_mode == SSR)
207 return get_seg_entry(sbi, segno)->ckpt_valid_blocks;
208
209 /* alloc_mode == LFS */
210 if (p->gc_mode == GC_GREEDY)
211 return get_valid_blocks(sbi, segno, sbi->segs_per_sec);
212 else
213 return get_cb_cost(sbi, segno);
214}
215
Jaegeuk Kim0a8165d2012-11-29 13:28:09 +0900216/*
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900217 * This function is called from two pathes.
218 * One is garbage collection and the other is SSR segment selection.
219 * When it is called during GC, it just gets a victim segment
220 * and it does not remove it from dirty seglist.
221 * When it is called from SSR segment selection, it finds a segment
222 * which has minimum valid blocks and removes it from dirty seglist.
223 */
224static int get_victim_by_default(struct f2fs_sb_info *sbi,
225 unsigned int *result, int gc_type, int type, char alloc_mode)
226{
227 struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
228 struct victim_sel_policy p;
229 unsigned int segno;
230 int nsearched = 0;
231
232 p.alloc_mode = alloc_mode;
233 select_policy(sbi, gc_type, type, &p);
234
235 p.min_segno = NULL_SEGNO;
236 p.min_cost = get_max_cost(sbi, &p);
237
238 mutex_lock(&dirty_i->seglist_lock);
239
240 if (p.alloc_mode == LFS && gc_type == FG_GC) {
241 p.min_segno = check_bg_victims(sbi);
242 if (p.min_segno != NULL_SEGNO)
243 goto got_it;
244 }
245
246 while (1) {
247 unsigned long cost;
248
249 segno = find_next_bit(p.dirty_segmap,
250 TOTAL_SEGS(sbi), p.offset);
251 if (segno >= TOTAL_SEGS(sbi)) {
252 if (sbi->last_victim[p.gc_mode]) {
253 sbi->last_victim[p.gc_mode] = 0;
254 p.offset = 0;
255 continue;
256 }
257 break;
258 }
259 p.offset = ((segno / p.ofs_unit) * p.ofs_unit) + p.ofs_unit;
260
261 if (test_bit(segno, dirty_i->victim_segmap[FG_GC]))
262 continue;
263 if (gc_type == BG_GC &&
264 test_bit(segno, dirty_i->victim_segmap[BG_GC]))
265 continue;
266 if (IS_CURSEC(sbi, GET_SECNO(sbi, segno)))
267 continue;
268
269 cost = get_gc_cost(sbi, segno, &p);
270
271 if (p.min_cost > cost) {
272 p.min_segno = segno;
273 p.min_cost = cost;
274 }
275
276 if (cost == get_max_cost(sbi, &p))
277 continue;
278
279 if (nsearched++ >= MAX_VICTIM_SEARCH) {
280 sbi->last_victim[p.gc_mode] = segno;
281 break;
282 }
283 }
284got_it:
285 if (p.min_segno != NULL_SEGNO) {
286 *result = (p.min_segno / p.ofs_unit) * p.ofs_unit;
287 if (p.alloc_mode == LFS) {
288 int i;
289 for (i = 0; i < p.ofs_unit; i++)
290 set_bit(*result + i,
291 dirty_i->victim_segmap[gc_type]);
292 }
293 }
294 mutex_unlock(&dirty_i->seglist_lock);
295
296 return (p.min_segno == NULL_SEGNO) ? 0 : 1;
297}
298
299static const struct victim_selection default_v_ops = {
300 .get_victim = get_victim_by_default,
301};
302
303static struct inode *find_gc_inode(nid_t ino, struct list_head *ilist)
304{
305 struct list_head *this;
306 struct inode_entry *ie;
307
308 list_for_each(this, ilist) {
309 ie = list_entry(this, struct inode_entry, list);
310 if (ie->inode->i_ino == ino)
311 return ie->inode;
312 }
313 return NULL;
314}
315
316static void add_gc_inode(struct inode *inode, struct list_head *ilist)
317{
318 struct list_head *this;
319 struct inode_entry *new_ie, *ie;
320
321 list_for_each(this, ilist) {
322 ie = list_entry(this, struct inode_entry, list);
323 if (ie->inode == inode) {
324 iput(inode);
325 return;
326 }
327 }
328repeat:
329 new_ie = kmem_cache_alloc(winode_slab, GFP_NOFS);
330 if (!new_ie) {
331 cond_resched();
332 goto repeat;
333 }
334 new_ie->inode = inode;
335 list_add_tail(&new_ie->list, ilist);
336}
337
338static void put_gc_inode(struct list_head *ilist)
339{
340 struct inode_entry *ie, *next_ie;
341 list_for_each_entry_safe(ie, next_ie, ilist, list) {
342 iput(ie->inode);
343 list_del(&ie->list);
344 kmem_cache_free(winode_slab, ie);
345 }
346}
347
348static int check_valid_map(struct f2fs_sb_info *sbi,
349 unsigned int segno, int offset)
350{
351 struct sit_info *sit_i = SIT_I(sbi);
352 struct seg_entry *sentry;
353 int ret;
354
355 mutex_lock(&sit_i->sentry_lock);
356 sentry = get_seg_entry(sbi, segno);
357 ret = f2fs_test_bit(offset, sentry->cur_valid_map);
358 mutex_unlock(&sit_i->sentry_lock);
359 return ret ? GC_OK : GC_NEXT;
360}
361
Jaegeuk Kim0a8165d2012-11-29 13:28:09 +0900362/*
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900363 * This function compares node address got in summary with that in NAT.
364 * On validity, copy that node with cold status, otherwise (invalid node)
365 * ignore that.
366 */
367static int gc_node_segment(struct f2fs_sb_info *sbi,
368 struct f2fs_summary *sum, unsigned int segno, int gc_type)
369{
370 bool initial = true;
371 struct f2fs_summary *entry;
372 int off;
373
374next_step:
375 entry = sum;
376 for (off = 0; off < sbi->blocks_per_seg; off++, entry++) {
377 nid_t nid = le32_to_cpu(entry->nid);
378 struct page *node_page;
379 int err;
380
381 /*
382 * It makes sure that free segments are able to write
383 * all the dirty node pages before CP after this CP.
384 * So let's check the space of dirty node pages.
385 */
386 if (should_do_checkpoint(sbi)) {
387 mutex_lock(&sbi->cp_mutex);
388 block_operations(sbi);
389 return GC_BLOCKED;
390 }
391
392 err = check_valid_map(sbi, segno, off);
Jaegeuk Kim2b506382012-12-26 14:39:50 +0900393 if (err == GC_NEXT)
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900394 continue;
395
396 if (initial) {
397 ra_node_page(sbi, nid);
398 continue;
399 }
400 node_page = get_node_page(sbi, nid);
401 if (IS_ERR(node_page))
402 continue;
403
404 /* set page dirty and write it */
405 if (!PageWriteback(node_page))
406 set_page_dirty(node_page);
407 f2fs_put_page(node_page, 1);
408 stat_inc_node_blk_count(sbi, 1);
409 }
410 if (initial) {
411 initial = false;
412 goto next_step;
413 }
414
415 if (gc_type == FG_GC) {
416 struct writeback_control wbc = {
417 .sync_mode = WB_SYNC_ALL,
418 .nr_to_write = LONG_MAX,
419 .for_reclaim = 0,
420 };
421 sync_node_pages(sbi, 0, &wbc);
422 }
423 return GC_DONE;
424}
425
Jaegeuk Kim0a8165d2012-11-29 13:28:09 +0900426/*
Jaegeuk Kim9af45ef2013-01-21 17:34:21 +0900427 * Calculate start block index indicating the given node offset.
428 * Be careful, caller should give this node offset only indicating direct node
429 * blocks. If any node offsets, which point the other types of node blocks such
430 * as indirect or double indirect node blocks, are given, it must be a caller's
431 * bug.
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900432 */
433block_t start_bidx_of_node(unsigned int node_ofs)
434{
Jaegeuk Kimce19a5d2012-12-26 12:03:22 +0900435 unsigned int indirect_blks = 2 * NIDS_PER_BLOCK + 4;
436 unsigned int bidx;
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900437
Jaegeuk Kimce19a5d2012-12-26 12:03:22 +0900438 if (node_ofs == 0)
439 return 0;
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900440
Jaegeuk Kimce19a5d2012-12-26 12:03:22 +0900441 if (node_ofs <= 2) {
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900442 bidx = node_ofs - 1;
443 } else if (node_ofs <= indirect_blks) {
Jaegeuk Kimce19a5d2012-12-26 12:03:22 +0900444 int dec = (node_ofs - 4) / (NIDS_PER_BLOCK + 1);
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900445 bidx = node_ofs - 2 - dec;
446 } else {
Jaegeuk Kimce19a5d2012-12-26 12:03:22 +0900447 int dec = (node_ofs - indirect_blks - 3) / (NIDS_PER_BLOCK + 1);
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900448 bidx = node_ofs - 5 - dec;
449 }
Jaegeuk Kimce19a5d2012-12-26 12:03:22 +0900450 return bidx * ADDRS_PER_BLOCK + ADDRS_PER_INODE;
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900451}
452
453static int check_dnode(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
454 struct node_info *dni, block_t blkaddr, unsigned int *nofs)
455{
456 struct page *node_page;
457 nid_t nid;
458 unsigned int ofs_in_node;
459 block_t source_blkaddr;
460
461 nid = le32_to_cpu(sum->nid);
462 ofs_in_node = le16_to_cpu(sum->ofs_in_node);
463
464 node_page = get_node_page(sbi, nid);
465 if (IS_ERR(node_page))
466 return GC_NEXT;
467
468 get_node_info(sbi, nid, dni);
469
470 if (sum->version != dni->version) {
471 f2fs_put_page(node_page, 1);
472 return GC_NEXT;
473 }
474
475 *nofs = ofs_of_node(node_page);
476 source_blkaddr = datablock_addr(node_page, ofs_in_node);
477 f2fs_put_page(node_page, 1);
478
479 if (source_blkaddr != blkaddr)
480 return GC_NEXT;
481 return GC_OK;
482}
483
484static void move_data_page(struct inode *inode, struct page *page, int gc_type)
485{
486 if (page->mapping != inode->i_mapping)
487 goto out;
488
489 if (inode != page->mapping->host)
490 goto out;
491
492 if (PageWriteback(page))
493 goto out;
494
495 if (gc_type == BG_GC) {
496 set_page_dirty(page);
497 set_cold_data(page);
498 } else {
499 struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
500 mutex_lock_op(sbi, DATA_WRITE);
501 if (clear_page_dirty_for_io(page) &&
502 S_ISDIR(inode->i_mode)) {
503 dec_page_count(sbi, F2FS_DIRTY_DENTS);
504 inode_dec_dirty_dents(inode);
505 }
506 set_cold_data(page);
507 do_write_data_page(page);
508 mutex_unlock_op(sbi, DATA_WRITE);
509 clear_cold_data(page);
510 }
511out:
512 f2fs_put_page(page, 1);
513}
514
Jaegeuk Kim0a8165d2012-11-29 13:28:09 +0900515/*
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900516 * This function tries to get parent node of victim data block, and identifies
517 * data block validity. If the block is valid, copy that with cold status and
518 * modify parent node.
519 * If the parent node is not valid or the data block address is different,
520 * the victim data block is ignored.
521 */
522static int gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
523 struct list_head *ilist, unsigned int segno, int gc_type)
524{
525 struct super_block *sb = sbi->sb;
526 struct f2fs_summary *entry;
527 block_t start_addr;
528 int err, off;
529 int phase = 0;
530
531 start_addr = START_BLOCK(sbi, segno);
532
533next_step:
534 entry = sum;
535 for (off = 0; off < sbi->blocks_per_seg; off++, entry++) {
536 struct page *data_page;
537 struct inode *inode;
538 struct node_info dni; /* dnode info for the data */
539 unsigned int ofs_in_node, nofs;
540 block_t start_bidx;
541
542 /*
543 * It makes sure that free segments are able to write
544 * all the dirty node pages before CP after this CP.
545 * So let's check the space of dirty node pages.
546 */
547 if (should_do_checkpoint(sbi)) {
548 mutex_lock(&sbi->cp_mutex);
549 block_operations(sbi);
550 err = GC_BLOCKED;
551 goto stop;
552 }
553
554 err = check_valid_map(sbi, segno, off);
Jaegeuk Kim2b506382012-12-26 14:39:50 +0900555 if (err == GC_NEXT)
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900556 continue;
557
558 if (phase == 0) {
559 ra_node_page(sbi, le32_to_cpu(entry->nid));
560 continue;
561 }
562
563 /* Get an inode by ino with checking validity */
564 err = check_dnode(sbi, entry, &dni, start_addr + off, &nofs);
Jaegeuk Kim2b506382012-12-26 14:39:50 +0900565 if (err == GC_NEXT)
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900566 continue;
567
568 if (phase == 1) {
569 ra_node_page(sbi, dni.ino);
570 continue;
571 }
572
573 start_bidx = start_bidx_of_node(nofs);
574 ofs_in_node = le16_to_cpu(entry->ofs_in_node);
575
576 if (phase == 2) {
577 inode = f2fs_iget_nowait(sb, dni.ino);
578 if (IS_ERR(inode))
579 continue;
580
581 data_page = find_data_page(inode,
582 start_bidx + ofs_in_node);
583 if (IS_ERR(data_page))
584 goto next_iput;
585
586 f2fs_put_page(data_page, 0);
587 add_gc_inode(inode, ilist);
588 } else {
589 inode = find_gc_inode(dni.ino, ilist);
590 if (inode) {
591 data_page = get_lock_data_page(inode,
592 start_bidx + ofs_in_node);
593 if (IS_ERR(data_page))
594 continue;
595 move_data_page(inode, data_page, gc_type);
596 stat_inc_data_blk_count(sbi, 1);
597 }
598 }
599 continue;
600next_iput:
601 iput(inode);
602 }
603 if (++phase < 4)
604 goto next_step;
605 err = GC_DONE;
606stop:
607 if (gc_type == FG_GC)
608 f2fs_submit_bio(sbi, DATA, true);
609 return err;
610}
611
612static int __get_victim(struct f2fs_sb_info *sbi, unsigned int *victim,
613 int gc_type, int type)
614{
615 struct sit_info *sit_i = SIT_I(sbi);
616 int ret;
617 mutex_lock(&sit_i->sentry_lock);
618 ret = DIRTY_I(sbi)->v_ops->get_victim(sbi, victim, gc_type, type, LFS);
619 mutex_unlock(&sit_i->sentry_lock);
620 return ret;
621}
622
623static int do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno,
624 struct list_head *ilist, int gc_type)
625{
626 struct page *sum_page;
627 struct f2fs_summary_block *sum;
628 int ret = GC_DONE;
629
630 /* read segment summary of victim */
631 sum_page = get_sum_page(sbi, segno);
632 if (IS_ERR(sum_page))
633 return GC_ERROR;
634
635 /*
636 * CP needs to lock sum_page. In this time, we don't need
637 * to lock this page, because this summary page is not gone anywhere.
638 * Also, this page is not gonna be updated before GC is done.
639 */
640 unlock_page(sum_page);
641 sum = page_address(sum_page);
642
643 switch (GET_SUM_TYPE((&sum->footer))) {
644 case SUM_TYPE_NODE:
645 ret = gc_node_segment(sbi, sum->entries, segno, gc_type);
646 break;
647 case SUM_TYPE_DATA:
648 ret = gc_data_segment(sbi, sum->entries, ilist, segno, gc_type);
649 break;
650 }
651 stat_inc_seg_count(sbi, GET_SUM_TYPE((&sum->footer)));
652 stat_inc_call_count(sbi->stat_info);
653
654 f2fs_put_page(sum_page, 0);
655 return ret;
656}
657
Jaegeuk Kim408e9372013-01-03 17:55:52 +0900658int f2fs_gc(struct f2fs_sb_info *sbi)
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900659{
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900660 struct list_head ilist;
Jaegeuk Kim408e9372013-01-03 17:55:52 +0900661 unsigned int segno, i;
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900662 int gc_type = BG_GC;
Jaegeuk Kim408e9372013-01-03 17:55:52 +0900663 int gc_status = GC_NONE;
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900664
665 INIT_LIST_HEAD(&ilist);
666gc_more:
Jaegeuk Kim408e9372013-01-03 17:55:52 +0900667 if (!(sbi->sb->s_flags & MS_ACTIVE))
668 goto stop;
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900669
670 if (has_not_enough_free_secs(sbi))
Jaegeuk Kim408e9372013-01-03 17:55:52 +0900671 gc_type = FG_GC;
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900672
Jaegeuk Kim408e9372013-01-03 17:55:52 +0900673 if (!__get_victim(sbi, &segno, gc_type, NO_CHECK_TYPE))
674 goto stop;
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900675
Jaegeuk Kim408e9372013-01-03 17:55:52 +0900676 for (i = 0; i < sbi->segs_per_sec; i++) {
677 /*
678 * do_garbage_collect will give us three gc_status:
679 * GC_ERROR, GC_DONE, and GC_BLOCKED.
680 * If GC is finished uncleanly, we have to return
681 * the victim to dirty segment list.
682 */
683 gc_status = do_garbage_collect(sbi, segno + i, &ilist, gc_type);
684 if (gc_status != GC_DONE)
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900685 break;
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900686 }
Jaegeuk Kim408e9372013-01-03 17:55:52 +0900687 if (has_not_enough_free_secs(sbi)) {
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900688 write_checkpoint(sbi, (gc_status == GC_BLOCKED), false);
Jaegeuk Kim408e9372013-01-03 17:55:52 +0900689 if (has_not_enough_free_secs(sbi))
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900690 goto gc_more;
691 }
Jaegeuk Kim408e9372013-01-03 17:55:52 +0900692stop:
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900693 mutex_unlock(&sbi->gc_mutex);
694
695 put_gc_inode(&ilist);
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900696 return gc_status;
697}
698
699void build_gc_manager(struct f2fs_sb_info *sbi)
700{
701 DIRTY_I(sbi)->v_ops = &default_v_ops;
702}
703
Namjae Jeon6e6093a2013-01-17 00:08:30 +0900704int __init create_gc_caches(void)
Jaegeuk Kim7bc09002012-11-02 17:13:01 +0900705{
706 winode_slab = f2fs_kmem_cache_create("f2fs_gc_inodes",
707 sizeof(struct inode_entry), NULL);
708 if (!winode_slab)
709 return -ENOMEM;
710 return 0;
711}
712
713void destroy_gc_caches(void)
714{
715 kmem_cache_destroy(winode_slab);
716}