ocfs2: fix locking for res->tracking and dlm->tracking_list
[linux/fpc-iii.git] / fs / f2fs / gc.c
blob928b9e046d8a85df8aa6f62e167b1ff7cdef1bd4
1 /*
2 * fs/f2fs/gc.c
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.
11 #include <linux/fs.h>
12 #include <linux/module.h>
13 #include <linux/backing-dev.h>
14 #include <linux/init.h>
15 #include <linux/f2fs_fs.h>
16 #include <linux/kthread.h>
17 #include <linux/delay.h>
18 #include <linux/freezer.h>
19 #include <linux/blkdev.h>
21 #include "f2fs.h"
22 #include "node.h"
23 #include "segment.h"
24 #include "gc.h"
25 #include <trace/events/f2fs.h>
27 static int gc_thread_func(void *data)
29 struct f2fs_sb_info *sbi = data;
30 struct f2fs_gc_kthread *gc_th = sbi->gc_thread;
31 wait_queue_head_t *wq = &sbi->gc_thread->gc_wait_queue_head;
32 long wait_ms;
34 wait_ms = gc_th->min_sleep_time;
36 do {
37 if (try_to_freeze())
38 continue;
39 else
40 wait_event_interruptible_timeout(*wq,
41 kthread_should_stop(),
42 msecs_to_jiffies(wait_ms));
43 if (kthread_should_stop())
44 break;
46 if (sbi->sb->s_writers.frozen >= SB_FREEZE_WRITE) {
47 increase_sleep_time(gc_th, &wait_ms);
48 continue;
52 * [GC triggering condition]
53 * 0. GC is not conducted currently.
54 * 1. There are enough dirty segments.
55 * 2. IO subsystem is idle by checking the # of writeback pages.
56 * 3. IO subsystem is idle by checking the # of requests in
57 * bdev's request list.
59 * Note) We have to avoid triggering GCs frequently.
60 * Because it is possible that some segments can be
61 * invalidated soon after by user update or deletion.
62 * So, I'd like to wait some time to collect dirty segments.
64 if (!mutex_trylock(&sbi->gc_mutex))
65 continue;
67 if (!is_idle(sbi)) {
68 increase_sleep_time(gc_th, &wait_ms);
69 mutex_unlock(&sbi->gc_mutex);
70 continue;
73 if (has_enough_invalid_blocks(sbi))
74 decrease_sleep_time(gc_th, &wait_ms);
75 else
76 increase_sleep_time(gc_th, &wait_ms);
78 stat_inc_bggc_count(sbi);
80 /* if return value is not zero, no victim was selected */
81 if (f2fs_gc(sbi, test_opt(sbi, FORCE_FG_GC)))
82 wait_ms = gc_th->no_gc_sleep_time;
84 trace_f2fs_background_gc(sbi->sb, wait_ms,
85 prefree_segments(sbi), free_segments(sbi));
87 /* balancing f2fs's metadata periodically */
88 f2fs_balance_fs_bg(sbi);
90 } while (!kthread_should_stop());
91 return 0;
94 int start_gc_thread(struct f2fs_sb_info *sbi)
96 struct f2fs_gc_kthread *gc_th;
97 dev_t dev = sbi->sb->s_bdev->bd_dev;
98 int err = 0;
100 gc_th = kmalloc(sizeof(struct f2fs_gc_kthread), GFP_KERNEL);
101 if (!gc_th) {
102 err = -ENOMEM;
103 goto out;
106 gc_th->min_sleep_time = DEF_GC_THREAD_MIN_SLEEP_TIME;
107 gc_th->max_sleep_time = DEF_GC_THREAD_MAX_SLEEP_TIME;
108 gc_th->no_gc_sleep_time = DEF_GC_THREAD_NOGC_SLEEP_TIME;
110 gc_th->gc_idle = 0;
112 sbi->gc_thread = gc_th;
113 init_waitqueue_head(&sbi->gc_thread->gc_wait_queue_head);
114 sbi->gc_thread->f2fs_gc_task = kthread_run(gc_thread_func, sbi,
115 "f2fs_gc-%u:%u", MAJOR(dev), MINOR(dev));
116 if (IS_ERR(gc_th->f2fs_gc_task)) {
117 err = PTR_ERR(gc_th->f2fs_gc_task);
118 kfree(gc_th);
119 sbi->gc_thread = NULL;
121 out:
122 return err;
125 void stop_gc_thread(struct f2fs_sb_info *sbi)
127 struct f2fs_gc_kthread *gc_th = sbi->gc_thread;
128 if (!gc_th)
129 return;
130 kthread_stop(gc_th->f2fs_gc_task);
131 kfree(gc_th);
132 sbi->gc_thread = NULL;
135 static int select_gc_type(struct f2fs_gc_kthread *gc_th, int gc_type)
137 int gc_mode = (gc_type == BG_GC) ? GC_CB : GC_GREEDY;
139 if (gc_th && gc_th->gc_idle) {
140 if (gc_th->gc_idle == 1)
141 gc_mode = GC_CB;
142 else if (gc_th->gc_idle == 2)
143 gc_mode = GC_GREEDY;
145 return gc_mode;
148 static void select_policy(struct f2fs_sb_info *sbi, int gc_type,
149 int type, struct victim_sel_policy *p)
151 struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
153 if (p->alloc_mode == SSR) {
154 p->gc_mode = GC_GREEDY;
155 p->dirty_segmap = dirty_i->dirty_segmap[type];
156 p->max_search = dirty_i->nr_dirty[type];
157 p->ofs_unit = 1;
158 } else {
159 p->gc_mode = select_gc_type(sbi->gc_thread, gc_type);
160 p->dirty_segmap = dirty_i->dirty_segmap[DIRTY];
161 p->max_search = dirty_i->nr_dirty[DIRTY];
162 p->ofs_unit = sbi->segs_per_sec;
165 if (p->max_search > sbi->max_victim_search)
166 p->max_search = sbi->max_victim_search;
168 p->offset = sbi->last_victim[p->gc_mode];
171 static unsigned int get_max_cost(struct f2fs_sb_info *sbi,
172 struct victim_sel_policy *p)
174 /* SSR allocates in a segment unit */
175 if (p->alloc_mode == SSR)
176 return 1 << sbi->log_blocks_per_seg;
177 if (p->gc_mode == GC_GREEDY)
178 return (1 << sbi->log_blocks_per_seg) * p->ofs_unit;
179 else if (p->gc_mode == GC_CB)
180 return UINT_MAX;
181 else /* No other gc_mode */
182 return 0;
185 static unsigned int check_bg_victims(struct f2fs_sb_info *sbi)
187 struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
188 unsigned int secno;
191 * If the gc_type is FG_GC, we can select victim segments
192 * selected by background GC before.
193 * Those segments guarantee they have small valid blocks.
195 for_each_set_bit(secno, dirty_i->victim_secmap, MAIN_SECS(sbi)) {
196 if (sec_usage_check(sbi, secno))
197 continue;
198 clear_bit(secno, dirty_i->victim_secmap);
199 return secno * sbi->segs_per_sec;
201 return NULL_SEGNO;
204 static unsigned int get_cb_cost(struct f2fs_sb_info *sbi, unsigned int segno)
206 struct sit_info *sit_i = SIT_I(sbi);
207 unsigned int secno = GET_SECNO(sbi, segno);
208 unsigned int start = secno * sbi->segs_per_sec;
209 unsigned long long mtime = 0;
210 unsigned int vblocks;
211 unsigned char age = 0;
212 unsigned char u;
213 unsigned int i;
215 for (i = 0; i < sbi->segs_per_sec; i++)
216 mtime += get_seg_entry(sbi, start + i)->mtime;
217 vblocks = get_valid_blocks(sbi, segno, sbi->segs_per_sec);
219 mtime = div_u64(mtime, sbi->segs_per_sec);
220 vblocks = div_u64(vblocks, sbi->segs_per_sec);
222 u = (vblocks * 100) >> sbi->log_blocks_per_seg;
224 /* Handle if the system time has changed by the user */
225 if (mtime < sit_i->min_mtime)
226 sit_i->min_mtime = mtime;
227 if (mtime > sit_i->max_mtime)
228 sit_i->max_mtime = mtime;
229 if (sit_i->max_mtime != sit_i->min_mtime)
230 age = 100 - div64_u64(100 * (mtime - sit_i->min_mtime),
231 sit_i->max_mtime - sit_i->min_mtime);
233 return UINT_MAX - ((100 * (100 - u) * age) / (100 + u));
236 static inline unsigned int get_gc_cost(struct f2fs_sb_info *sbi,
237 unsigned int segno, struct victim_sel_policy *p)
239 if (p->alloc_mode == SSR)
240 return get_seg_entry(sbi, segno)->ckpt_valid_blocks;
242 /* alloc_mode == LFS */
243 if (p->gc_mode == GC_GREEDY)
244 return get_valid_blocks(sbi, segno, sbi->segs_per_sec);
245 else
246 return get_cb_cost(sbi, segno);
250 * This function is called from two paths.
251 * One is garbage collection and the other is SSR segment selection.
252 * When it is called during GC, it just gets a victim segment
253 * and it does not remove it from dirty seglist.
254 * When it is called from SSR segment selection, it finds a segment
255 * which has minimum valid blocks and removes it from dirty seglist.
257 static int get_victim_by_default(struct f2fs_sb_info *sbi,
258 unsigned int *result, int gc_type, int type, char alloc_mode)
260 struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
261 struct victim_sel_policy p;
262 unsigned int secno, max_cost;
263 unsigned int last_segment = MAIN_SEGS(sbi);
264 int nsearched = 0;
266 mutex_lock(&dirty_i->seglist_lock);
268 p.alloc_mode = alloc_mode;
269 select_policy(sbi, gc_type, type, &p);
271 p.min_segno = NULL_SEGNO;
272 p.min_cost = max_cost = get_max_cost(sbi, &p);
274 if (p.max_search == 0)
275 goto out;
277 if (p.alloc_mode == LFS && gc_type == FG_GC) {
278 p.min_segno = check_bg_victims(sbi);
279 if (p.min_segno != NULL_SEGNO)
280 goto got_it;
283 while (1) {
284 unsigned long cost;
285 unsigned int segno;
287 segno = find_next_bit(p.dirty_segmap, last_segment, p.offset);
288 if (segno >= last_segment) {
289 if (sbi->last_victim[p.gc_mode]) {
290 last_segment = sbi->last_victim[p.gc_mode];
291 sbi->last_victim[p.gc_mode] = 0;
292 p.offset = 0;
293 continue;
295 break;
298 p.offset = segno + p.ofs_unit;
299 if (p.ofs_unit > 1)
300 p.offset -= segno % p.ofs_unit;
302 secno = GET_SECNO(sbi, segno);
304 if (sec_usage_check(sbi, secno))
305 continue;
306 if (gc_type == BG_GC && test_bit(secno, dirty_i->victim_secmap))
307 continue;
309 cost = get_gc_cost(sbi, segno, &p);
311 if (p.min_cost > cost) {
312 p.min_segno = segno;
313 p.min_cost = cost;
314 } else if (unlikely(cost == max_cost)) {
315 continue;
318 if (nsearched++ >= p.max_search) {
319 sbi->last_victim[p.gc_mode] = segno;
320 break;
323 if (p.min_segno != NULL_SEGNO) {
324 got_it:
325 if (p.alloc_mode == LFS) {
326 secno = GET_SECNO(sbi, p.min_segno);
327 if (gc_type == FG_GC)
328 sbi->cur_victim_sec = secno;
329 else
330 set_bit(secno, dirty_i->victim_secmap);
332 *result = (p.min_segno / p.ofs_unit) * p.ofs_unit;
334 trace_f2fs_get_victim(sbi->sb, type, gc_type, &p,
335 sbi->cur_victim_sec,
336 prefree_segments(sbi), free_segments(sbi));
338 out:
339 mutex_unlock(&dirty_i->seglist_lock);
341 return (p.min_segno == NULL_SEGNO) ? 0 : 1;
344 static const struct victim_selection default_v_ops = {
345 .get_victim = get_victim_by_default,
348 static struct inode *find_gc_inode(struct gc_inode_list *gc_list, nid_t ino)
350 struct inode_entry *ie;
352 ie = radix_tree_lookup(&gc_list->iroot, ino);
353 if (ie)
354 return ie->inode;
355 return NULL;
358 static void add_gc_inode(struct gc_inode_list *gc_list, struct inode *inode)
360 struct inode_entry *new_ie;
362 if (inode == find_gc_inode(gc_list, inode->i_ino)) {
363 iput(inode);
364 return;
366 new_ie = f2fs_kmem_cache_alloc(inode_entry_slab, GFP_NOFS);
367 new_ie->inode = inode;
369 f2fs_radix_tree_insert(&gc_list->iroot, inode->i_ino, new_ie);
370 list_add_tail(&new_ie->list, &gc_list->ilist);
373 static void put_gc_inode(struct gc_inode_list *gc_list)
375 struct inode_entry *ie, *next_ie;
376 list_for_each_entry_safe(ie, next_ie, &gc_list->ilist, list) {
377 radix_tree_delete(&gc_list->iroot, ie->inode->i_ino);
378 iput(ie->inode);
379 list_del(&ie->list);
380 kmem_cache_free(inode_entry_slab, ie);
384 static int check_valid_map(struct f2fs_sb_info *sbi,
385 unsigned int segno, int offset)
387 struct sit_info *sit_i = SIT_I(sbi);
388 struct seg_entry *sentry;
389 int ret;
391 mutex_lock(&sit_i->sentry_lock);
392 sentry = get_seg_entry(sbi, segno);
393 ret = f2fs_test_bit(offset, sentry->cur_valid_map);
394 mutex_unlock(&sit_i->sentry_lock);
395 return ret;
399 * This function compares node address got in summary with that in NAT.
400 * On validity, copy that node with cold status, otherwise (invalid node)
401 * ignore that.
403 static int gc_node_segment(struct f2fs_sb_info *sbi,
404 struct f2fs_summary *sum, unsigned int segno, int gc_type)
406 bool initial = true;
407 struct f2fs_summary *entry;
408 block_t start_addr;
409 int off;
411 start_addr = START_BLOCK(sbi, segno);
413 next_step:
414 entry = sum;
416 for (off = 0; off < sbi->blocks_per_seg; off++, entry++) {
417 nid_t nid = le32_to_cpu(entry->nid);
418 struct page *node_page;
419 struct node_info ni;
421 /* stop BG_GC if there is not enough free sections. */
422 if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0))
423 return 0;
425 if (check_valid_map(sbi, segno, off) == 0)
426 continue;
428 if (initial) {
429 ra_node_page(sbi, nid);
430 continue;
432 node_page = get_node_page(sbi, nid);
433 if (IS_ERR(node_page))
434 continue;
436 /* block may become invalid during get_node_page */
437 if (check_valid_map(sbi, segno, off) == 0) {
438 f2fs_put_page(node_page, 1);
439 continue;
442 get_node_info(sbi, nid, &ni);
443 if (ni.blk_addr != start_addr + off) {
444 f2fs_put_page(node_page, 1);
445 continue;
448 /* set page dirty and write it */
449 if (gc_type == FG_GC) {
450 f2fs_wait_on_page_writeback(node_page, NODE);
451 set_page_dirty(node_page);
452 } else {
453 if (!PageWriteback(node_page))
454 set_page_dirty(node_page);
456 f2fs_put_page(node_page, 1);
457 stat_inc_node_blk_count(sbi, 1, gc_type);
460 if (initial) {
461 initial = false;
462 goto next_step;
465 if (gc_type == FG_GC) {
466 struct writeback_control wbc = {
467 .sync_mode = WB_SYNC_ALL,
468 .nr_to_write = LONG_MAX,
469 .for_reclaim = 0,
471 sync_node_pages(sbi, 0, &wbc);
473 /* return 1 only if FG_GC succefully reclaimed one */
474 if (get_valid_blocks(sbi, segno, 1) == 0)
475 return 1;
477 return 0;
481 * Calculate start block index indicating the given node offset.
482 * Be careful, caller should give this node offset only indicating direct node
483 * blocks. If any node offsets, which point the other types of node blocks such
484 * as indirect or double indirect node blocks, are given, it must be a caller's
485 * bug.
487 block_t start_bidx_of_node(unsigned int node_ofs, struct f2fs_inode_info *fi)
489 unsigned int indirect_blks = 2 * NIDS_PER_BLOCK + 4;
490 unsigned int bidx;
492 if (node_ofs == 0)
493 return 0;
495 if (node_ofs <= 2) {
496 bidx = node_ofs - 1;
497 } else if (node_ofs <= indirect_blks) {
498 int dec = (node_ofs - 4) / (NIDS_PER_BLOCK + 1);
499 bidx = node_ofs - 2 - dec;
500 } else {
501 int dec = (node_ofs - indirect_blks - 3) / (NIDS_PER_BLOCK + 1);
502 bidx = node_ofs - 5 - dec;
504 return bidx * ADDRS_PER_BLOCK + ADDRS_PER_INODE(fi);
507 static bool is_alive(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
508 struct node_info *dni, block_t blkaddr, unsigned int *nofs)
510 struct page *node_page;
511 nid_t nid;
512 unsigned int ofs_in_node;
513 block_t source_blkaddr;
515 nid = le32_to_cpu(sum->nid);
516 ofs_in_node = le16_to_cpu(sum->ofs_in_node);
518 node_page = get_node_page(sbi, nid);
519 if (IS_ERR(node_page))
520 return false;
522 get_node_info(sbi, nid, dni);
524 if (sum->version != dni->version) {
525 f2fs_msg(sbi->sb, KERN_WARNING,
526 "%s: valid data with mismatched node version.",
527 __func__);
528 set_sbi_flag(sbi, SBI_NEED_FSCK);
531 *nofs = ofs_of_node(node_page);
532 source_blkaddr = datablock_addr(node_page, ofs_in_node);
533 f2fs_put_page(node_page, 1);
535 if (source_blkaddr != blkaddr)
536 return false;
537 return true;
540 static void move_encrypted_block(struct inode *inode, block_t bidx)
542 struct f2fs_io_info fio = {
543 .sbi = F2FS_I_SB(inode),
544 .type = DATA,
545 .rw = READ_SYNC,
546 .encrypted_page = NULL,
548 struct dnode_of_data dn;
549 struct f2fs_summary sum;
550 struct node_info ni;
551 struct page *page;
552 int err;
554 /* do not read out */
555 page = f2fs_grab_cache_page(inode->i_mapping, bidx, false);
556 if (!page)
557 return;
559 set_new_dnode(&dn, inode, NULL, NULL, 0);
560 err = get_dnode_of_data(&dn, bidx, LOOKUP_NODE);
561 if (err)
562 goto out;
564 if (unlikely(dn.data_blkaddr == NULL_ADDR)) {
565 ClearPageUptodate(page);
566 goto put_out;
570 * don't cache encrypted data into meta inode until previous dirty
571 * data were writebacked to avoid racing between GC and flush.
573 f2fs_wait_on_page_writeback(page, DATA);
575 get_node_info(fio.sbi, dn.nid, &ni);
576 set_summary(&sum, dn.nid, dn.ofs_in_node, ni.version);
578 /* read page */
579 fio.page = page;
580 fio.blk_addr = dn.data_blkaddr;
582 fio.encrypted_page = pagecache_get_page(META_MAPPING(fio.sbi),
583 fio.blk_addr,
584 FGP_LOCK|FGP_CREAT,
585 GFP_NOFS);
586 if (!fio.encrypted_page)
587 goto put_out;
589 err = f2fs_submit_page_bio(&fio);
590 if (err)
591 goto put_page_out;
593 /* write page */
594 lock_page(fio.encrypted_page);
596 if (unlikely(!PageUptodate(fio.encrypted_page)))
597 goto put_page_out;
598 if (unlikely(fio.encrypted_page->mapping != META_MAPPING(fio.sbi)))
599 goto put_page_out;
601 set_page_dirty(fio.encrypted_page);
602 f2fs_wait_on_page_writeback(fio.encrypted_page, DATA);
603 if (clear_page_dirty_for_io(fio.encrypted_page))
604 dec_page_count(fio.sbi, F2FS_DIRTY_META);
606 set_page_writeback(fio.encrypted_page);
608 /* allocate block address */
609 f2fs_wait_on_page_writeback(dn.node_page, NODE);
610 allocate_data_block(fio.sbi, NULL, fio.blk_addr,
611 &fio.blk_addr, &sum, CURSEG_COLD_DATA);
612 fio.rw = WRITE_SYNC;
613 f2fs_submit_page_mbio(&fio);
615 dn.data_blkaddr = fio.blk_addr;
616 set_data_blkaddr(&dn);
617 f2fs_update_extent_cache(&dn);
618 set_inode_flag(F2FS_I(inode), FI_APPEND_WRITE);
619 if (page->index == 0)
620 set_inode_flag(F2FS_I(inode), FI_FIRST_BLOCK_WRITTEN);
621 put_page_out:
622 f2fs_put_page(fio.encrypted_page, 1);
623 put_out:
624 f2fs_put_dnode(&dn);
625 out:
626 f2fs_put_page(page, 1);
629 static void move_data_page(struct inode *inode, block_t bidx, int gc_type)
631 struct page *page;
633 page = get_lock_data_page(inode, bidx, true);
634 if (IS_ERR(page))
635 return;
637 if (gc_type == BG_GC) {
638 if (PageWriteback(page))
639 goto out;
640 set_page_dirty(page);
641 set_cold_data(page);
642 } else {
643 struct f2fs_io_info fio = {
644 .sbi = F2FS_I_SB(inode),
645 .type = DATA,
646 .rw = WRITE_SYNC,
647 .page = page,
648 .encrypted_page = NULL,
650 set_page_dirty(page);
651 f2fs_wait_on_page_writeback(page, DATA);
652 if (clear_page_dirty_for_io(page))
653 inode_dec_dirty_pages(inode);
654 set_cold_data(page);
655 do_write_data_page(&fio);
656 clear_cold_data(page);
658 out:
659 f2fs_put_page(page, 1);
663 * This function tries to get parent node of victim data block, and identifies
664 * data block validity. If the block is valid, copy that with cold status and
665 * modify parent node.
666 * If the parent node is not valid or the data block address is different,
667 * the victim data block is ignored.
669 static int gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum,
670 struct gc_inode_list *gc_list, unsigned int segno, int gc_type)
672 struct super_block *sb = sbi->sb;
673 struct f2fs_summary *entry;
674 block_t start_addr;
675 int off;
676 int phase = 0;
678 start_addr = START_BLOCK(sbi, segno);
680 next_step:
681 entry = sum;
683 for (off = 0; off < sbi->blocks_per_seg; off++, entry++) {
684 struct page *data_page;
685 struct inode *inode;
686 struct node_info dni; /* dnode info for the data */
687 unsigned int ofs_in_node, nofs;
688 block_t start_bidx;
690 /* stop BG_GC if there is not enough free sections. */
691 if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0))
692 return 0;
694 if (check_valid_map(sbi, segno, off) == 0)
695 continue;
697 if (phase == 0) {
698 ra_node_page(sbi, le32_to_cpu(entry->nid));
699 continue;
702 /* Get an inode by ino with checking validity */
703 if (!is_alive(sbi, entry, &dni, start_addr + off, &nofs))
704 continue;
706 if (phase == 1) {
707 ra_node_page(sbi, dni.ino);
708 continue;
711 ofs_in_node = le16_to_cpu(entry->ofs_in_node);
713 if (phase == 2) {
714 inode = f2fs_iget(sb, dni.ino);
715 if (IS_ERR(inode) || is_bad_inode(inode))
716 continue;
718 /* if encrypted inode, let's go phase 3 */
719 if (f2fs_encrypted_inode(inode) &&
720 S_ISREG(inode->i_mode)) {
721 add_gc_inode(gc_list, inode);
722 continue;
725 start_bidx = start_bidx_of_node(nofs, F2FS_I(inode));
726 data_page = get_read_data_page(inode,
727 start_bidx + ofs_in_node, READA, true);
728 if (IS_ERR(data_page)) {
729 iput(inode);
730 continue;
733 f2fs_put_page(data_page, 0);
734 add_gc_inode(gc_list, inode);
735 continue;
738 /* phase 3 */
739 inode = find_gc_inode(gc_list, dni.ino);
740 if (inode) {
741 start_bidx = start_bidx_of_node(nofs, F2FS_I(inode))
742 + ofs_in_node;
743 if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
744 move_encrypted_block(inode, start_bidx);
745 else
746 move_data_page(inode, start_bidx, gc_type);
747 stat_inc_data_blk_count(sbi, 1, gc_type);
751 if (++phase < 4)
752 goto next_step;
754 if (gc_type == FG_GC) {
755 f2fs_submit_merged_bio(sbi, DATA, WRITE);
757 /* return 1 only if FG_GC succefully reclaimed one */
758 if (get_valid_blocks(sbi, segno, 1) == 0)
759 return 1;
761 return 0;
764 static int __get_victim(struct f2fs_sb_info *sbi, unsigned int *victim,
765 int gc_type)
767 struct sit_info *sit_i = SIT_I(sbi);
768 int ret;
770 mutex_lock(&sit_i->sentry_lock);
771 ret = DIRTY_I(sbi)->v_ops->get_victim(sbi, victim, gc_type,
772 NO_CHECK_TYPE, LFS);
773 mutex_unlock(&sit_i->sentry_lock);
774 return ret;
777 static int do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno,
778 struct gc_inode_list *gc_list, int gc_type)
780 struct page *sum_page;
781 struct f2fs_summary_block *sum;
782 struct blk_plug plug;
783 int nfree = 0;
785 /* read segment summary of victim */
786 sum_page = get_sum_page(sbi, segno);
788 blk_start_plug(&plug);
790 sum = page_address(sum_page);
793 * this is to avoid deadlock:
794 * - lock_page(sum_page) - f2fs_replace_block
795 * - check_valid_map() - mutex_lock(sentry_lock)
796 * - mutex_lock(sentry_lock) - change_curseg()
797 * - lock_page(sum_page)
799 unlock_page(sum_page);
801 switch (GET_SUM_TYPE((&sum->footer))) {
802 case SUM_TYPE_NODE:
803 nfree = gc_node_segment(sbi, sum->entries, segno, gc_type);
804 break;
805 case SUM_TYPE_DATA:
806 nfree = gc_data_segment(sbi, sum->entries, gc_list,
807 segno, gc_type);
808 break;
810 blk_finish_plug(&plug);
812 stat_inc_seg_count(sbi, GET_SUM_TYPE((&sum->footer)), gc_type);
813 stat_inc_call_count(sbi->stat_info);
815 f2fs_put_page(sum_page, 0);
816 return nfree;
819 int f2fs_gc(struct f2fs_sb_info *sbi, bool sync)
821 unsigned int segno, i;
822 int gc_type = sync ? FG_GC : BG_GC;
823 int sec_freed = 0;
824 int ret = -EINVAL;
825 struct cp_control cpc;
826 struct gc_inode_list gc_list = {
827 .ilist = LIST_HEAD_INIT(gc_list.ilist),
828 .iroot = RADIX_TREE_INIT(GFP_NOFS),
831 cpc.reason = __get_cp_reason(sbi);
832 gc_more:
833 segno = NULL_SEGNO;
835 if (unlikely(!(sbi->sb->s_flags & MS_ACTIVE)))
836 goto stop;
837 if (unlikely(f2fs_cp_error(sbi)))
838 goto stop;
840 if (gc_type == BG_GC && has_not_enough_free_secs(sbi, sec_freed)) {
841 gc_type = FG_GC;
842 if (__get_victim(sbi, &segno, gc_type) || prefree_segments(sbi))
843 write_checkpoint(sbi, &cpc);
846 if (segno == NULL_SEGNO && !__get_victim(sbi, &segno, gc_type))
847 goto stop;
848 ret = 0;
850 /* readahead multi ssa blocks those have contiguous address */
851 if (sbi->segs_per_sec > 1)
852 ra_meta_pages(sbi, GET_SUM_BLOCK(sbi, segno), sbi->segs_per_sec,
853 META_SSA, true);
855 for (i = 0; i < sbi->segs_per_sec; i++) {
857 * for FG_GC case, halt gcing left segments once failed one
858 * of segments in selected section to avoid long latency.
860 if (!do_garbage_collect(sbi, segno + i, &gc_list, gc_type) &&
861 gc_type == FG_GC)
862 break;
865 if (i == sbi->segs_per_sec && gc_type == FG_GC)
866 sec_freed++;
868 if (gc_type == FG_GC)
869 sbi->cur_victim_sec = NULL_SEGNO;
871 if (!sync) {
872 if (has_not_enough_free_secs(sbi, sec_freed))
873 goto gc_more;
875 if (gc_type == FG_GC)
876 write_checkpoint(sbi, &cpc);
878 stop:
879 mutex_unlock(&sbi->gc_mutex);
881 put_gc_inode(&gc_list);
883 if (sync)
884 ret = sec_freed ? 0 : -EAGAIN;
885 return ret;
888 void build_gc_manager(struct f2fs_sb_info *sbi)
890 DIRTY_I(sbi)->v_ops = &default_v_ops;