Commit | Line | Data |
---|---|---|
7bc09003 JK |
1 | /** |
2 | * 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 | ||
27 | static struct kmem_cache *winode_slab; | |
28 | ||
29 | static 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 | ||
81 | if (f2fs_gc(sbi, 1) == GC_NONE) | |
82 | 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 | ||
90 | int start_gc_thread(struct f2fs_sb_info *sbi) | |
91 | { | |
92 | struct f2fs_gc_kthread *gc_th = NULL; | |
93 | ||
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 | ||
109 | void 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 | ||
119 | static int select_gc_type(int gc_type) | |
120 | { | |
121 | return (gc_type == BG_GC) ? GC_CB : GC_GREEDY; | |
122 | } | |
123 | ||
124 | static 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 | ||
141 | static 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 | ||
152 | static 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 | ||
171 | static 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 | ||
203 | static 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 | ||
216 | /** | |
217 | * 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 | */ | |
224 | static 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 | } | |
284 | got_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 | ||
299 | static const struct victim_selection default_v_ops = { | |
300 | .get_victim = get_victim_by_default, | |
301 | }; | |
302 | ||
303 | static 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 | ||
316 | static 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 | } | |
328 | repeat: | |
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 | ||
338 | static 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 | ||
348 | static 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 | ||
362 | /** | |
363 | * 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 | */ | |
367 | static 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 | ||
374 | next_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); | |
393 | if (err == GC_ERROR) | |
394 | return err; | |
395 | else if (err == GC_NEXT) | |
396 | continue; | |
397 | ||
398 | if (initial) { | |
399 | ra_node_page(sbi, nid); | |
400 | continue; | |
401 | } | |
402 | node_page = get_node_page(sbi, nid); | |
403 | if (IS_ERR(node_page)) | |
404 | continue; | |
405 | ||
406 | /* set page dirty and write it */ | |
407 | if (!PageWriteback(node_page)) | |
408 | set_page_dirty(node_page); | |
409 | f2fs_put_page(node_page, 1); | |
410 | stat_inc_node_blk_count(sbi, 1); | |
411 | } | |
412 | if (initial) { | |
413 | initial = false; | |
414 | goto next_step; | |
415 | } | |
416 | ||
417 | if (gc_type == FG_GC) { | |
418 | struct writeback_control wbc = { | |
419 | .sync_mode = WB_SYNC_ALL, | |
420 | .nr_to_write = LONG_MAX, | |
421 | .for_reclaim = 0, | |
422 | }; | |
423 | sync_node_pages(sbi, 0, &wbc); | |
424 | } | |
425 | return GC_DONE; | |
426 | } | |
427 | ||
428 | /** | |
429 | * Calculate start block index that this node page contains | |
430 | */ | |
431 | block_t start_bidx_of_node(unsigned int node_ofs) | |
432 | { | |
433 | block_t start_bidx; | |
434 | unsigned int bidx, indirect_blks; | |
435 | int dec; | |
436 | ||
437 | indirect_blks = 2 * NIDS_PER_BLOCK + 4; | |
438 | ||
439 | start_bidx = 1; | |
440 | if (node_ofs == 0) { | |
441 | start_bidx = 0; | |
442 | } else if (node_ofs <= 2) { | |
443 | bidx = node_ofs - 1; | |
444 | } else if (node_ofs <= indirect_blks) { | |
445 | dec = (node_ofs - 4) / (NIDS_PER_BLOCK + 1); | |
446 | bidx = node_ofs - 2 - dec; | |
447 | } else { | |
448 | dec = (node_ofs - indirect_blks - 3) / (NIDS_PER_BLOCK + 1); | |
449 | bidx = node_ofs - 5 - dec; | |
450 | } | |
451 | ||
452 | if (start_bidx) | |
453 | start_bidx = bidx * ADDRS_PER_BLOCK + ADDRS_PER_INODE; | |
454 | return start_bidx; | |
455 | } | |
456 | ||
457 | static int check_dnode(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, | |
458 | struct node_info *dni, block_t blkaddr, unsigned int *nofs) | |
459 | { | |
460 | struct page *node_page; | |
461 | nid_t nid; | |
462 | unsigned int ofs_in_node; | |
463 | block_t source_blkaddr; | |
464 | ||
465 | nid = le32_to_cpu(sum->nid); | |
466 | ofs_in_node = le16_to_cpu(sum->ofs_in_node); | |
467 | ||
468 | node_page = get_node_page(sbi, nid); | |
469 | if (IS_ERR(node_page)) | |
470 | return GC_NEXT; | |
471 | ||
472 | get_node_info(sbi, nid, dni); | |
473 | ||
474 | if (sum->version != dni->version) { | |
475 | f2fs_put_page(node_page, 1); | |
476 | return GC_NEXT; | |
477 | } | |
478 | ||
479 | *nofs = ofs_of_node(node_page); | |
480 | source_blkaddr = datablock_addr(node_page, ofs_in_node); | |
481 | f2fs_put_page(node_page, 1); | |
482 | ||
483 | if (source_blkaddr != blkaddr) | |
484 | return GC_NEXT; | |
485 | return GC_OK; | |
486 | } | |
487 | ||
488 | static void move_data_page(struct inode *inode, struct page *page, int gc_type) | |
489 | { | |
490 | if (page->mapping != inode->i_mapping) | |
491 | goto out; | |
492 | ||
493 | if (inode != page->mapping->host) | |
494 | goto out; | |
495 | ||
496 | if (PageWriteback(page)) | |
497 | goto out; | |
498 | ||
499 | if (gc_type == BG_GC) { | |
500 | set_page_dirty(page); | |
501 | set_cold_data(page); | |
502 | } else { | |
503 | struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb); | |
504 | mutex_lock_op(sbi, DATA_WRITE); | |
505 | if (clear_page_dirty_for_io(page) && | |
506 | S_ISDIR(inode->i_mode)) { | |
507 | dec_page_count(sbi, F2FS_DIRTY_DENTS); | |
508 | inode_dec_dirty_dents(inode); | |
509 | } | |
510 | set_cold_data(page); | |
511 | do_write_data_page(page); | |
512 | mutex_unlock_op(sbi, DATA_WRITE); | |
513 | clear_cold_data(page); | |
514 | } | |
515 | out: | |
516 | f2fs_put_page(page, 1); | |
517 | } | |
518 | ||
519 | /** | |
520 | * This function tries to get parent node of victim data block, and identifies | |
521 | * data block validity. If the block is valid, copy that with cold status and | |
522 | * modify parent node. | |
523 | * If the parent node is not valid or the data block address is different, | |
524 | * the victim data block is ignored. | |
525 | */ | |
526 | static int gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, | |
527 | struct list_head *ilist, unsigned int segno, int gc_type) | |
528 | { | |
529 | struct super_block *sb = sbi->sb; | |
530 | struct f2fs_summary *entry; | |
531 | block_t start_addr; | |
532 | int err, off; | |
533 | int phase = 0; | |
534 | ||
535 | start_addr = START_BLOCK(sbi, segno); | |
536 | ||
537 | next_step: | |
538 | entry = sum; | |
539 | for (off = 0; off < sbi->blocks_per_seg; off++, entry++) { | |
540 | struct page *data_page; | |
541 | struct inode *inode; | |
542 | struct node_info dni; /* dnode info for the data */ | |
543 | unsigned int ofs_in_node, nofs; | |
544 | block_t start_bidx; | |
545 | ||
546 | /* | |
547 | * It makes sure that free segments are able to write | |
548 | * all the dirty node pages before CP after this CP. | |
549 | * So let's check the space of dirty node pages. | |
550 | */ | |
551 | if (should_do_checkpoint(sbi)) { | |
552 | mutex_lock(&sbi->cp_mutex); | |
553 | block_operations(sbi); | |
554 | err = GC_BLOCKED; | |
555 | goto stop; | |
556 | } | |
557 | ||
558 | err = check_valid_map(sbi, segno, off); | |
559 | if (err == GC_ERROR) | |
560 | goto stop; | |
561 | else if (err == GC_NEXT) | |
562 | continue; | |
563 | ||
564 | if (phase == 0) { | |
565 | ra_node_page(sbi, le32_to_cpu(entry->nid)); | |
566 | continue; | |
567 | } | |
568 | ||
569 | /* Get an inode by ino with checking validity */ | |
570 | err = check_dnode(sbi, entry, &dni, start_addr + off, &nofs); | |
571 | if (err == GC_ERROR) | |
572 | goto stop; | |
573 | else if (err == GC_NEXT) | |
574 | continue; | |
575 | ||
576 | if (phase == 1) { | |
577 | ra_node_page(sbi, dni.ino); | |
578 | continue; | |
579 | } | |
580 | ||
581 | start_bidx = start_bidx_of_node(nofs); | |
582 | ofs_in_node = le16_to_cpu(entry->ofs_in_node); | |
583 | ||
584 | if (phase == 2) { | |
585 | inode = f2fs_iget_nowait(sb, dni.ino); | |
586 | if (IS_ERR(inode)) | |
587 | continue; | |
588 | ||
589 | data_page = find_data_page(inode, | |
590 | start_bidx + ofs_in_node); | |
591 | if (IS_ERR(data_page)) | |
592 | goto next_iput; | |
593 | ||
594 | f2fs_put_page(data_page, 0); | |
595 | add_gc_inode(inode, ilist); | |
596 | } else { | |
597 | inode = find_gc_inode(dni.ino, ilist); | |
598 | if (inode) { | |
599 | data_page = get_lock_data_page(inode, | |
600 | start_bidx + ofs_in_node); | |
601 | if (IS_ERR(data_page)) | |
602 | continue; | |
603 | move_data_page(inode, data_page, gc_type); | |
604 | stat_inc_data_blk_count(sbi, 1); | |
605 | } | |
606 | } | |
607 | continue; | |
608 | next_iput: | |
609 | iput(inode); | |
610 | } | |
611 | if (++phase < 4) | |
612 | goto next_step; | |
613 | err = GC_DONE; | |
614 | stop: | |
615 | if (gc_type == FG_GC) | |
616 | f2fs_submit_bio(sbi, DATA, true); | |
617 | return err; | |
618 | } | |
619 | ||
620 | static int __get_victim(struct f2fs_sb_info *sbi, unsigned int *victim, | |
621 | int gc_type, int type) | |
622 | { | |
623 | struct sit_info *sit_i = SIT_I(sbi); | |
624 | int ret; | |
625 | mutex_lock(&sit_i->sentry_lock); | |
626 | ret = DIRTY_I(sbi)->v_ops->get_victim(sbi, victim, gc_type, type, LFS); | |
627 | mutex_unlock(&sit_i->sentry_lock); | |
628 | return ret; | |
629 | } | |
630 | ||
631 | static int do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno, | |
632 | struct list_head *ilist, int gc_type) | |
633 | { | |
634 | struct page *sum_page; | |
635 | struct f2fs_summary_block *sum; | |
636 | int ret = GC_DONE; | |
637 | ||
638 | /* read segment summary of victim */ | |
639 | sum_page = get_sum_page(sbi, segno); | |
640 | if (IS_ERR(sum_page)) | |
641 | return GC_ERROR; | |
642 | ||
643 | /* | |
644 | * CP needs to lock sum_page. In this time, we don't need | |
645 | * to lock this page, because this summary page is not gone anywhere. | |
646 | * Also, this page is not gonna be updated before GC is done. | |
647 | */ | |
648 | unlock_page(sum_page); | |
649 | sum = page_address(sum_page); | |
650 | ||
651 | switch (GET_SUM_TYPE((&sum->footer))) { | |
652 | case SUM_TYPE_NODE: | |
653 | ret = gc_node_segment(sbi, sum->entries, segno, gc_type); | |
654 | break; | |
655 | case SUM_TYPE_DATA: | |
656 | ret = gc_data_segment(sbi, sum->entries, ilist, segno, gc_type); | |
657 | break; | |
658 | } | |
659 | stat_inc_seg_count(sbi, GET_SUM_TYPE((&sum->footer))); | |
660 | stat_inc_call_count(sbi->stat_info); | |
661 | ||
662 | f2fs_put_page(sum_page, 0); | |
663 | return ret; | |
664 | } | |
665 | ||
666 | int f2fs_gc(struct f2fs_sb_info *sbi, int nGC) | |
667 | { | |
668 | unsigned int segno; | |
669 | int old_free_secs, cur_free_secs; | |
670 | int gc_status, nfree; | |
671 | struct list_head ilist; | |
672 | int gc_type = BG_GC; | |
673 | ||
674 | INIT_LIST_HEAD(&ilist); | |
675 | gc_more: | |
676 | nfree = 0; | |
677 | gc_status = GC_NONE; | |
678 | ||
679 | if (has_not_enough_free_secs(sbi)) | |
680 | old_free_secs = reserved_sections(sbi); | |
681 | else | |
682 | old_free_secs = free_sections(sbi); | |
683 | ||
684 | while (sbi->sb->s_flags & MS_ACTIVE) { | |
685 | int i; | |
686 | if (has_not_enough_free_secs(sbi)) | |
687 | gc_type = FG_GC; | |
688 | ||
689 | cur_free_secs = free_sections(sbi) + nfree; | |
690 | ||
691 | /* We got free space successfully. */ | |
692 | if (nGC < cur_free_secs - old_free_secs) | |
693 | break; | |
694 | ||
695 | if (!__get_victim(sbi, &segno, gc_type, NO_CHECK_TYPE)) | |
696 | break; | |
697 | ||
698 | for (i = 0; i < sbi->segs_per_sec; i++) { | |
699 | /* | |
700 | * do_garbage_collect will give us three gc_status: | |
701 | * GC_ERROR, GC_DONE, and GC_BLOCKED. | |
702 | * If GC is finished uncleanly, we have to return | |
703 | * the victim to dirty segment list. | |
704 | */ | |
705 | gc_status = do_garbage_collect(sbi, segno + i, | |
706 | &ilist, gc_type); | |
707 | if (gc_status != GC_DONE) | |
708 | goto stop; | |
709 | nfree++; | |
710 | } | |
711 | } | |
712 | stop: | |
713 | if (has_not_enough_free_secs(sbi) || gc_status == GC_BLOCKED) { | |
714 | write_checkpoint(sbi, (gc_status == GC_BLOCKED), false); | |
715 | if (nfree) | |
716 | goto gc_more; | |
717 | } | |
718 | mutex_unlock(&sbi->gc_mutex); | |
719 | ||
720 | put_gc_inode(&ilist); | |
721 | BUG_ON(!list_empty(&ilist)); | |
722 | return gc_status; | |
723 | } | |
724 | ||
725 | void build_gc_manager(struct f2fs_sb_info *sbi) | |
726 | { | |
727 | DIRTY_I(sbi)->v_ops = &default_v_ops; | |
728 | } | |
729 | ||
730 | int create_gc_caches(void) | |
731 | { | |
732 | winode_slab = f2fs_kmem_cache_create("f2fs_gc_inodes", | |
733 | sizeof(struct inode_entry), NULL); | |
734 | if (!winode_slab) | |
735 | return -ENOMEM; | |
736 | return 0; | |
737 | } | |
738 | ||
739 | void destroy_gc_caches(void) | |
740 | { | |
741 | kmem_cache_destroy(winode_slab); | |
742 | } |