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/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> 20 21#include "f2fs.h" 22#include "node.h" 23#include "segment.h" 24#include "gc.h" 25#include <trace/events/f2fs.h> 26 27static int gc_thread_func(void *data) 28{ 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; 33 34 wait_ms = gc_th->min_sleep_time; 35 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; 45 46 if (sbi->sb->s_writers.frozen >= SB_FREEZE_WRITE) { 47 increase_sleep_time(gc_th, &wait_ms); 48 continue; 49 } 50 51 /* 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. 58 * 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. 63 */ 64 if (!mutex_trylock(&sbi->gc_mutex)) 65 continue; 66 67 if (!is_idle(sbi)) { 68 increase_sleep_time(gc_th, &wait_ms); 69 mutex_unlock(&sbi->gc_mutex); 70 continue; 71 } 72 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); 77 78 stat_inc_bggc_count(sbi); 79 80 /* if return value is not zero, no victim was selected */ 81 if (f2fs_gc(sbi)) 82 wait_ms = gc_th->no_gc_sleep_time; 83 84 /* balancing f2fs's metadata periodically */ 85 f2fs_balance_fs_bg(sbi); 86 87 } while (!kthread_should_stop()); 88 return 0; 89} 90 91int start_gc_thread(struct f2fs_sb_info *sbi) 92{ 93 struct f2fs_gc_kthread *gc_th; 94 dev_t dev = sbi->sb->s_bdev->bd_dev; 95 int err = 0; 96 97 gc_th = kmalloc(sizeof(struct f2fs_gc_kthread), GFP_KERNEL); 98 if (!gc_th) { 99 err = -ENOMEM; 100 goto out; 101 } 102 103 gc_th->min_sleep_time = DEF_GC_THREAD_MIN_SLEEP_TIME; 104 gc_th->max_sleep_time = DEF_GC_THREAD_MAX_SLEEP_TIME; 105 gc_th->no_gc_sleep_time = DEF_GC_THREAD_NOGC_SLEEP_TIME; 106 107 gc_th->gc_idle = 0; 108 109 sbi->gc_thread = gc_th; 110 init_waitqueue_head(&sbi->gc_thread->gc_wait_queue_head); 111 sbi->gc_thread->f2fs_gc_task = kthread_run(gc_thread_func, sbi, 112 "f2fs_gc-%u:%u", MAJOR(dev), MINOR(dev)); 113 if (IS_ERR(gc_th->f2fs_gc_task)) { 114 err = PTR_ERR(gc_th->f2fs_gc_task); 115 kfree(gc_th); 116 sbi->gc_thread = NULL; 117 } 118out: 119 return err; 120} 121 122void stop_gc_thread(struct f2fs_sb_info *sbi) 123{ 124 struct f2fs_gc_kthread *gc_th = sbi->gc_thread; 125 if (!gc_th) 126 return; 127 kthread_stop(gc_th->f2fs_gc_task); 128 kfree(gc_th); 129 sbi->gc_thread = NULL; 130} 131 132static int select_gc_type(struct f2fs_gc_kthread *gc_th, int gc_type) 133{ 134 int gc_mode = (gc_type == BG_GC) ? GC_CB : GC_GREEDY; 135 136 if (gc_th && gc_th->gc_idle) { 137 if (gc_th->gc_idle == 1) 138 gc_mode = GC_CB; 139 else if (gc_th->gc_idle == 2) 140 gc_mode = GC_GREEDY; 141 } 142 return gc_mode; 143} 144 145static void select_policy(struct f2fs_sb_info *sbi, int gc_type, 146 int type, struct victim_sel_policy *p) 147{ 148 struct dirty_seglist_info *dirty_i = DIRTY_I(sbi); 149 150 if (p->alloc_mode == SSR) { 151 p->gc_mode = GC_GREEDY; 152 p->dirty_segmap = dirty_i->dirty_segmap[type]; 153 p->max_search = dirty_i->nr_dirty[type]; 154 p->ofs_unit = 1; 155 } else { 156 p->gc_mode = select_gc_type(sbi->gc_thread, gc_type); 157 p->dirty_segmap = dirty_i->dirty_segmap[DIRTY]; 158 p->max_search = dirty_i->nr_dirty[DIRTY]; 159 p->ofs_unit = sbi->segs_per_sec; 160 } 161 162 if (p->max_search > sbi->max_victim_search) 163 p->max_search = sbi->max_victim_search; 164 165 p->offset = sbi->last_victim[p->gc_mode]; 166} 167 168static unsigned int get_max_cost(struct f2fs_sb_info *sbi, 169 struct victim_sel_policy *p) 170{ 171 /* SSR allocates in a segment unit */ 172 if (p->alloc_mode == SSR) 173 return 1 << sbi->log_blocks_per_seg; 174 if (p->gc_mode == GC_GREEDY) 175 return (1 << sbi->log_blocks_per_seg) * p->ofs_unit; 176 else if (p->gc_mode == GC_CB) 177 return UINT_MAX; 178 else /* No other gc_mode */ 179 return 0; 180} 181 182static unsigned int check_bg_victims(struct f2fs_sb_info *sbi) 183{ 184 struct dirty_seglist_info *dirty_i = DIRTY_I(sbi); 185 unsigned int secno; 186 187 /* 188 * If the gc_type is FG_GC, we can select victim segments 189 * selected by background GC before. 190 * Those segments guarantee they have small valid blocks. 191 */ 192 for_each_set_bit(secno, dirty_i->victim_secmap, MAIN_SECS(sbi)) { 193 if (sec_usage_check(sbi, secno)) 194 continue; 195 clear_bit(secno, dirty_i->victim_secmap); 196 return secno * sbi->segs_per_sec; 197 } 198 return NULL_SEGNO; 199} 200 201static unsigned int get_cb_cost(struct f2fs_sb_info *sbi, unsigned int segno) 202{ 203 struct sit_info *sit_i = SIT_I(sbi); 204 unsigned int secno = GET_SECNO(sbi, segno); 205 unsigned int start = secno * sbi->segs_per_sec; 206 unsigned long long mtime = 0; 207 unsigned int vblocks; 208 unsigned char age = 0; 209 unsigned char u; 210 unsigned int i; 211 212 for (i = 0; i < sbi->segs_per_sec; i++) 213 mtime += get_seg_entry(sbi, start + i)->mtime; 214 vblocks = get_valid_blocks(sbi, segno, sbi->segs_per_sec); 215 216 mtime = div_u64(mtime, sbi->segs_per_sec); 217 vblocks = div_u64(vblocks, sbi->segs_per_sec); 218 219 u = (vblocks * 100) >> sbi->log_blocks_per_seg; 220 221 /* Handle if the system time has changed by the user */ 222 if (mtime < sit_i->min_mtime) 223 sit_i->min_mtime = mtime; 224 if (mtime > sit_i->max_mtime) 225 sit_i->max_mtime = mtime; 226 if (sit_i->max_mtime != sit_i->min_mtime) 227 age = 100 - div64_u64(100 * (mtime - sit_i->min_mtime), 228 sit_i->max_mtime - sit_i->min_mtime); 229 230 return UINT_MAX - ((100 * (100 - u) * age) / (100 + u)); 231} 232 233static inline unsigned int get_gc_cost(struct f2fs_sb_info *sbi, 234 unsigned int segno, struct victim_sel_policy *p) 235{ 236 if (p->alloc_mode == SSR) 237 return get_seg_entry(sbi, segno)->ckpt_valid_blocks; 238 239 /* alloc_mode == LFS */ 240 if (p->gc_mode == GC_GREEDY) 241 return get_valid_blocks(sbi, segno, sbi->segs_per_sec); 242 else 243 return get_cb_cost(sbi, segno); 244} 245 246/* 247 * This function is called from two paths. 248 * One is garbage collection and the other is SSR segment selection. 249 * When it is called during GC, it just gets a victim segment 250 * and it does not remove it from dirty seglist. 251 * When it is called from SSR segment selection, it finds a segment 252 * which has minimum valid blocks and removes it from dirty seglist. 253 */ 254static int get_victim_by_default(struct f2fs_sb_info *sbi, 255 unsigned int *result, int gc_type, int type, char alloc_mode) 256{ 257 struct dirty_seglist_info *dirty_i = DIRTY_I(sbi); 258 struct victim_sel_policy p; 259 unsigned int secno, max_cost; 260 int nsearched = 0; 261 262 mutex_lock(&dirty_i->seglist_lock); 263 264 p.alloc_mode = alloc_mode; 265 select_policy(sbi, gc_type, type, &p); 266 267 p.min_segno = NULL_SEGNO; 268 p.min_cost = max_cost = get_max_cost(sbi, &p); 269 270 if (p.alloc_mode == LFS && gc_type == FG_GC) { 271 p.min_segno = check_bg_victims(sbi); 272 if (p.min_segno != NULL_SEGNO) 273 goto got_it; 274 } 275 276 while (1) { 277 unsigned long cost; 278 unsigned int segno; 279 280 segno = find_next_bit(p.dirty_segmap, MAIN_SEGS(sbi), p.offset); 281 if (segno >= MAIN_SEGS(sbi)) { 282 if (sbi->last_victim[p.gc_mode]) { 283 sbi->last_victim[p.gc_mode] = 0; 284 p.offset = 0; 285 continue; 286 } 287 break; 288 } 289 290 p.offset = segno + p.ofs_unit; 291 if (p.ofs_unit > 1) 292 p.offset -= segno % p.ofs_unit; 293 294 secno = GET_SECNO(sbi, segno); 295 296 if (sec_usage_check(sbi, secno)) 297 continue; 298 if (gc_type == BG_GC && test_bit(secno, dirty_i->victim_secmap)) 299 continue; 300 301 cost = get_gc_cost(sbi, segno, &p); 302 303 if (p.min_cost > cost) { 304 p.min_segno = segno; 305 p.min_cost = cost; 306 } else if (unlikely(cost == max_cost)) { 307 continue; 308 } 309 310 if (nsearched++ >= p.max_search) { 311 sbi->last_victim[p.gc_mode] = segno; 312 break; 313 } 314 } 315 if (p.min_segno != NULL_SEGNO) { 316got_it: 317 if (p.alloc_mode == LFS) { 318 secno = GET_SECNO(sbi, p.min_segno); 319 if (gc_type == FG_GC) 320 sbi->cur_victim_sec = secno; 321 else 322 set_bit(secno, dirty_i->victim_secmap); 323 } 324 *result = (p.min_segno / p.ofs_unit) * p.ofs_unit; 325 326 trace_f2fs_get_victim(sbi->sb, type, gc_type, &p, 327 sbi->cur_victim_sec, 328 prefree_segments(sbi), free_segments(sbi)); 329 } 330 mutex_unlock(&dirty_i->seglist_lock); 331 332 return (p.min_segno == NULL_SEGNO) ? 0 : 1; 333} 334 335static const struct victim_selection default_v_ops = { 336 .get_victim = get_victim_by_default, 337}; 338 339static struct inode *find_gc_inode(struct gc_inode_list *gc_list, nid_t ino) 340{ 341 struct inode_entry *ie; 342 343 ie = radix_tree_lookup(&gc_list->iroot, ino); 344 if (ie) 345 return ie->inode; 346 return NULL; 347} 348 349static void add_gc_inode(struct gc_inode_list *gc_list, struct inode *inode) 350{ 351 struct inode_entry *new_ie; 352 353 if (inode == find_gc_inode(gc_list, inode->i_ino)) { 354 iput(inode); 355 return; 356 } 357 new_ie = f2fs_kmem_cache_alloc(inode_entry_slab, GFP_NOFS); 358 new_ie->inode = inode; 359 360 f2fs_radix_tree_insert(&gc_list->iroot, inode->i_ino, new_ie); 361 list_add_tail(&new_ie->list, &gc_list->ilist); 362} 363 364static void put_gc_inode(struct gc_inode_list *gc_list) 365{ 366 struct inode_entry *ie, *next_ie; 367 list_for_each_entry_safe(ie, next_ie, &gc_list->ilist, list) { 368 radix_tree_delete(&gc_list->iroot, ie->inode->i_ino); 369 iput(ie->inode); 370 list_del(&ie->list); 371 kmem_cache_free(inode_entry_slab, ie); 372 } 373} 374 375static int check_valid_map(struct f2fs_sb_info *sbi, 376 unsigned int segno, int offset) 377{ 378 struct sit_info *sit_i = SIT_I(sbi); 379 struct seg_entry *sentry; 380 int ret; 381 382 mutex_lock(&sit_i->sentry_lock); 383 sentry = get_seg_entry(sbi, segno); 384 ret = f2fs_test_bit(offset, sentry->cur_valid_map); 385 mutex_unlock(&sit_i->sentry_lock); 386 return ret; 387} 388 389/* 390 * This function compares node address got in summary with that in NAT. 391 * On validity, copy that node with cold status, otherwise (invalid node) 392 * ignore that. 393 */ 394static void gc_node_segment(struct f2fs_sb_info *sbi, 395 struct f2fs_summary *sum, unsigned int segno, int gc_type) 396{ 397 bool initial = true; 398 struct f2fs_summary *entry; 399 int off; 400 401next_step: 402 entry = sum; 403 404 for (off = 0; off < sbi->blocks_per_seg; off++, entry++) { 405 nid_t nid = le32_to_cpu(entry->nid); 406 struct page *node_page; 407 408 /* stop BG_GC if there is not enough free sections. */ 409 if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0)) 410 return; 411 412 if (check_valid_map(sbi, segno, off) == 0) 413 continue; 414 415 if (initial) { 416 ra_node_page(sbi, nid); 417 continue; 418 } 419 node_page = get_node_page(sbi, nid); 420 if (IS_ERR(node_page)) 421 continue; 422 423 /* block may become invalid during get_node_page */ 424 if (check_valid_map(sbi, segno, off) == 0) { 425 f2fs_put_page(node_page, 1); 426 continue; 427 } 428 429 /* set page dirty and write it */ 430 if (gc_type == FG_GC) { 431 f2fs_wait_on_page_writeback(node_page, NODE); 432 set_page_dirty(node_page); 433 } else { 434 if (!PageWriteback(node_page)) 435 set_page_dirty(node_page); 436 } 437 f2fs_put_page(node_page, 1); 438 stat_inc_node_blk_count(sbi, 1, gc_type); 439 } 440 441 if (initial) { 442 initial = false; 443 goto next_step; 444 } 445 446 if (gc_type == FG_GC) { 447 struct writeback_control wbc = { 448 .sync_mode = WB_SYNC_ALL, 449 .nr_to_write = LONG_MAX, 450 .for_reclaim = 0, 451 }; 452 sync_node_pages(sbi, 0, &wbc); 453 454 /* 455 * In the case of FG_GC, it'd be better to reclaim this victim 456 * completely. 457 */ 458 if (get_valid_blocks(sbi, segno, 1) != 0) 459 goto next_step; 460 } 461} 462 463/* 464 * Calculate start block index indicating the given node offset. 465 * Be careful, caller should give this node offset only indicating direct node 466 * blocks. If any node offsets, which point the other types of node blocks such 467 * as indirect or double indirect node blocks, are given, it must be a caller's 468 * bug. 469 */ 470block_t start_bidx_of_node(unsigned int node_ofs, struct f2fs_inode_info *fi) 471{ 472 unsigned int indirect_blks = 2 * NIDS_PER_BLOCK + 4; 473 unsigned int bidx; 474 475 if (node_ofs == 0) 476 return 0; 477 478 if (node_ofs <= 2) { 479 bidx = node_ofs - 1; 480 } else if (node_ofs <= indirect_blks) { 481 int dec = (node_ofs - 4) / (NIDS_PER_BLOCK + 1); 482 bidx = node_ofs - 2 - dec; 483 } else { 484 int dec = (node_ofs - indirect_blks - 3) / (NIDS_PER_BLOCK + 1); 485 bidx = node_ofs - 5 - dec; 486 } 487 return bidx * ADDRS_PER_BLOCK + ADDRS_PER_INODE(fi); 488} 489 490static int check_dnode(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, 491 struct node_info *dni, block_t blkaddr, unsigned int *nofs) 492{ 493 struct page *node_page; 494 nid_t nid; 495 unsigned int ofs_in_node; 496 block_t source_blkaddr; 497 498 nid = le32_to_cpu(sum->nid); 499 ofs_in_node = le16_to_cpu(sum->ofs_in_node); 500 501 node_page = get_node_page(sbi, nid); 502 if (IS_ERR(node_page)) 503 return 0; 504 505 get_node_info(sbi, nid, dni); 506 507 if (sum->version != dni->version) { 508 f2fs_put_page(node_page, 1); 509 return 0; 510 } 511 512 *nofs = ofs_of_node(node_page); 513 source_blkaddr = datablock_addr(node_page, ofs_in_node); 514 f2fs_put_page(node_page, 1); 515 516 if (source_blkaddr != blkaddr) 517 return 0; 518 return 1; 519} 520 521static void move_data_page(struct inode *inode, struct page *page, int gc_type) 522{ 523 struct f2fs_io_info fio = { 524 .type = DATA, 525 .rw = WRITE_SYNC, 526 }; 527 528 if (gc_type == BG_GC) { 529 if (PageWriteback(page)) 530 goto out; 531 set_page_dirty(page); 532 set_cold_data(page); 533 } else { 534 f2fs_wait_on_page_writeback(page, DATA); 535 536 if (clear_page_dirty_for_io(page)) 537 inode_dec_dirty_pages(inode); 538 set_cold_data(page); 539 do_write_data_page(page, &fio); 540 clear_cold_data(page); 541 } 542out: 543 f2fs_put_page(page, 1); 544} 545 546/* 547 * This function tries to get parent node of victim data block, and identifies 548 * data block validity. If the block is valid, copy that with cold status and 549 * modify parent node. 550 * If the parent node is not valid or the data block address is different, 551 * the victim data block is ignored. 552 */ 553static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, 554 struct gc_inode_list *gc_list, unsigned int segno, int gc_type) 555{ 556 struct super_block *sb = sbi->sb; 557 struct f2fs_summary *entry; 558 block_t start_addr; 559 int off; 560 int phase = 0; 561 562 start_addr = START_BLOCK(sbi, segno); 563 564next_step: 565 entry = sum; 566 567 for (off = 0; off < sbi->blocks_per_seg; off++, entry++) { 568 struct page *data_page; 569 struct inode *inode; 570 struct node_info dni; /* dnode info for the data */ 571 unsigned int ofs_in_node, nofs; 572 block_t start_bidx; 573 574 /* stop BG_GC if there is not enough free sections. */ 575 if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0)) 576 return; 577 578 if (check_valid_map(sbi, segno, off) == 0) 579 continue; 580 581 if (phase == 0) { 582 ra_node_page(sbi, le32_to_cpu(entry->nid)); 583 continue; 584 } 585 586 /* Get an inode by ino with checking validity */ 587 if (check_dnode(sbi, entry, &dni, start_addr + off, &nofs) == 0) 588 continue; 589 590 if (phase == 1) { 591 ra_node_page(sbi, dni.ino); 592 continue; 593 } 594 595 ofs_in_node = le16_to_cpu(entry->ofs_in_node); 596 597 if (phase == 2) { 598 inode = f2fs_iget(sb, dni.ino); 599 if (IS_ERR(inode) || is_bad_inode(inode)) 600 continue; 601 602 start_bidx = start_bidx_of_node(nofs, F2FS_I(inode)); 603 604 data_page = find_data_page(inode, 605 start_bidx + ofs_in_node, false); 606 if (IS_ERR(data_page)) { 607 iput(inode); 608 continue; 609 } 610 611 f2fs_put_page(data_page, 0); 612 add_gc_inode(gc_list, inode); 613 continue; 614 } 615 616 /* phase 3 */ 617 inode = find_gc_inode(gc_list, dni.ino); 618 if (inode) { 619 start_bidx = start_bidx_of_node(nofs, F2FS_I(inode)); 620 data_page = get_lock_data_page(inode, 621 start_bidx + ofs_in_node); 622 if (IS_ERR(data_page)) 623 continue; 624 move_data_page(inode, data_page, gc_type); 625 stat_inc_data_blk_count(sbi, 1, gc_type); 626 } 627 } 628 629 if (++phase < 4) 630 goto next_step; 631 632 if (gc_type == FG_GC) { 633 f2fs_submit_merged_bio(sbi, DATA, WRITE); 634 635 /* 636 * In the case of FG_GC, it'd be better to reclaim this victim 637 * completely. 638 */ 639 if (get_valid_blocks(sbi, segno, 1) != 0) { 640 phase = 2; 641 goto next_step; 642 } 643 } 644} 645 646static int __get_victim(struct f2fs_sb_info *sbi, unsigned int *victim, 647 int gc_type) 648{ 649 struct sit_info *sit_i = SIT_I(sbi); 650 int ret; 651 652 mutex_lock(&sit_i->sentry_lock); 653 ret = DIRTY_I(sbi)->v_ops->get_victim(sbi, victim, gc_type, 654 NO_CHECK_TYPE, LFS); 655 mutex_unlock(&sit_i->sentry_lock); 656 return ret; 657} 658 659static void do_garbage_collect(struct f2fs_sb_info *sbi, unsigned int segno, 660 struct gc_inode_list *gc_list, int gc_type) 661{ 662 struct page *sum_page; 663 struct f2fs_summary_block *sum; 664 struct blk_plug plug; 665 666 /* read segment summary of victim */ 667 sum_page = get_sum_page(sbi, segno); 668 669 blk_start_plug(&plug); 670 671 sum = page_address(sum_page); 672 673 switch (GET_SUM_TYPE((&sum->footer))) { 674 case SUM_TYPE_NODE: 675 gc_node_segment(sbi, sum->entries, segno, gc_type); 676 break; 677 case SUM_TYPE_DATA: 678 gc_data_segment(sbi, sum->entries, gc_list, segno, gc_type); 679 break; 680 } 681 blk_finish_plug(&plug); 682 683 stat_inc_seg_count(sbi, GET_SUM_TYPE((&sum->footer)), gc_type); 684 stat_inc_call_count(sbi->stat_info); 685 686 f2fs_put_page(sum_page, 1); 687} 688 689int f2fs_gc(struct f2fs_sb_info *sbi) 690{ 691 unsigned int segno, i; 692 int gc_type = BG_GC; 693 int nfree = 0; 694 int ret = -1; 695 struct cp_control cpc; 696 struct gc_inode_list gc_list = { 697 .ilist = LIST_HEAD_INIT(gc_list.ilist), 698 .iroot = RADIX_TREE_INIT(GFP_NOFS), 699 }; 700 701 cpc.reason = __get_cp_reason(sbi); 702gc_more: 703 if (unlikely(!(sbi->sb->s_flags & MS_ACTIVE))) 704 goto stop; 705 if (unlikely(f2fs_cp_error(sbi))) 706 goto stop; 707 708 if (gc_type == BG_GC && has_not_enough_free_secs(sbi, nfree)) { 709 gc_type = FG_GC; 710 write_checkpoint(sbi, &cpc); 711 } 712 713 if (!__get_victim(sbi, &segno, gc_type)) 714 goto stop; 715 ret = 0; 716 717 /* readahead multi ssa blocks those have contiguous address */ 718 if (sbi->segs_per_sec > 1) 719 ra_meta_pages(sbi, GET_SUM_BLOCK(sbi, segno), sbi->segs_per_sec, 720 META_SSA); 721 722 for (i = 0; i < sbi->segs_per_sec; i++) 723 do_garbage_collect(sbi, segno + i, &gc_list, gc_type); 724 725 if (gc_type == FG_GC) { 726 sbi->cur_victim_sec = NULL_SEGNO; 727 nfree++; 728 WARN_ON(get_valid_blocks(sbi, segno, sbi->segs_per_sec)); 729 } 730 731 if (has_not_enough_free_secs(sbi, nfree)) 732 goto gc_more; 733 734 if (gc_type == FG_GC) 735 write_checkpoint(sbi, &cpc); 736stop: 737 mutex_unlock(&sbi->gc_mutex); 738 739 put_gc_inode(&gc_list); 740 return ret; 741} 742 743void build_gc_manager(struct f2fs_sb_info *sbi) 744{ 745 DIRTY_I(sbi)->v_ops = &default_v_ops; 746} 747