fs/f2fs/segment.c

   1 /*
   2  * fs/f2fs/segment.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/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>
  19
  20 #include "f2fs.h"
  21 #include "segment.h"
  22 #include "node.h"
  23 #include "trace.h"
  24 #include <trace/events/f2fs.h>
  25
  26 #define __reverse_ffz(x) __reverse_ffs(~(x))
  27
  28 static struct kmem_cache *discard_entry_slab;
  29 static struct kmem_cache *sit_entry_set_slab;
  30 static struct kmem_cache *inmem_entry_slab;
  31
  32 /*
  33  * __reverse_ffs is copied from include/asm-generic/bitops/__ffs.h since
  34  * MSB and LSB are reversed in a byte by f2fs_set_bit.
  35  */
  36 static inline unsigned long __reverse_ffs(unsigned long word)
  37 {
  38         int num = 0;
  39
  40 #if BITS_PER_LONG == 64
  41         if ((word & 0xffffffff) == 0) {
  42                 num += 32;
  43                 word >>= 32;
  44         }
  45 #endif
  46         if ((word & 0xffff) == 0) {
  47                 num += 16;
  48                 word >>= 16;
  49         }
  50         if ((word & 0xff) == 0) {
  51                 num += 8;
  52                 word >>= 8;
  53         }
  54         if ((word & 0xf0) == 0)
  55                 num += 4;
  56         else
  57                 word >>= 4;
  58         if ((word & 0xc) == 0)
  59                 num += 2;
  60         else
  61                 word >>= 2;
  62         if ((word & 0x2) == 0)
  63                 num += 1;
  64         return num;
  65 }
  66
  67 /*
  68  * __find_rev_next(_zero)_bit is copied from lib/find_next_bit.c because
  69  * f2fs_set_bit makes MSB and LSB reversed in a byte.
  70  * Example:
  71  *                             LSB <--> MSB
  72  *   f2fs_set_bit(0, bitmap) => 0000 0001
  73  *   f2fs_set_bit(7, bitmap) => 1000 0000
  74  */
  75 static unsigned long __find_rev_next_bit(const unsigned long *addr,
  76                         unsigned long size, unsigned long offset)
  77 {
  78         while (!f2fs_test_bit(offset, (unsigned char *)addr))
  79                 offset++;
  80
  81         if (offset > size)
  82                 offset = size;
  83
  84         return offset;
  85 #if 0
  86         const unsigned long *p = addr + BIT_WORD(offset);
  87         unsigned long result = offset & ~(BITS_PER_LONG - 1);
  88         unsigned long tmp;
  89         unsigned long mask, submask;
  90         unsigned long quot, rest;
  91
  92         if (offset >= size)
  93                 return size;
  94
  95         size -= result;
  96         offset %= BITS_PER_LONG;
  97         if (!offset)
  98                 goto aligned;
  99
 100         tmp = *(p++);
 101         quot = (offset >> 3) << 3;
 102         rest = offset & 0x7;
 103         mask = ~0UL << quot;
 104         submask = (unsigned char)(0xff << rest) >> rest;
 105         submask <<= quot;
 106         mask &= submask;
 107         tmp &= mask;
 108         if (size < BITS_PER_LONG)
 109                 goto found_first;
 110         if (tmp)
 111                 goto found_middle;
 112
 113         size -= BITS_PER_LONG;
 114         result += BITS_PER_LONG;
 115 aligned:
 116         while (size & ~(BITS_PER_LONG-1)) {
 117                 tmp = *(p++);
 118                 if (tmp)
 119                         goto found_middle;
 120                 result += BITS_PER_LONG;
 121                 size -= BITS_PER_LONG;
 122         }
 123         if (!size)
 124                 return result;
 125         tmp = *p;
 126 found_first:
 127         tmp &= (~0UL >> (BITS_PER_LONG - size));
 128         if (tmp == 0UL)         /* Are any bits set? */
 129                 return result + size;   /* Nope. */
 130 found_middle:
 131         return result + __reverse_ffs(tmp);
 132 #endif
 133 }
 134
 135 static unsigned long __find_rev_next_zero_bit(const unsigned long *addr,
 136                         unsigned long size, unsigned long offset)
 137 {
 138         while (f2fs_test_bit(offset, (unsigned char *)addr))
 139                 offset++;
 140
 141         if (offset > size)
 142                 offset = size;
 143
 144         return offset;
 145 #if 0
 146         const unsigned long *p = addr + BIT_WORD(offset);
 147         unsigned long result = offset & ~(BITS_PER_LONG - 1);
 148         unsigned long tmp;
 149         unsigned long mask, submask;
 150         unsigned long quot, rest;
 151
 152         if (offset >= size)
 153                 return size;
 154
 155         size -= result;
 156         offset %= BITS_PER_LONG;
 157         if (!offset)
 158                 goto aligned;
 159
 160         tmp = *(p++);
 161         quot = (offset >> 3) << 3;
 162         rest = offset & 0x7;
 163         mask = ~(~0UL << quot);
 164         submask = (unsigned char)~((unsigned char)(0xff << rest) >> rest);
 165         submask <<= quot;
 166         mask += submask;
 167         tmp |= mask;
 168         if (size < BITS_PER_LONG)
 169                 goto found_first;
 170         if (~tmp)
 171                 goto found_middle;
 172
 173         size -= BITS_PER_LONG;
 174         result += BITS_PER_LONG;
 175 aligned:
 176         while (size & ~(BITS_PER_LONG - 1)) {
 177                 tmp = *(p++);
 178                 if (~tmp)
 179                         goto found_middle;
 180                 result += BITS_PER_LONG;
 181                 size -= BITS_PER_LONG;
 182         }
 183         if (!size)
 184                 return result;
 185         tmp = *p;
 186
 187 found_first:
 188         tmp |= ~0UL << size;
 189         if (tmp == ~0UL)        /* Are any bits zero? */
 190                 return result + size;   /* Nope. */
 191 found_middle:
 192         return result + __reverse_ffz(tmp);
 193 #endif
 194 }
 195
 196 void register_inmem_page(struct inode *inode, struct page *page)
 197 {
 198         struct f2fs_inode_info *fi = F2FS_I(inode);
 199         struct inmem_pages *new;
 200
 201         f2fs_trace_pid(page);
 202
 203         set_page_private(page, (unsigned long)ATOMIC_WRITTEN_PAGE);
 204         SetPagePrivate(page);
 205
 206         new = f2fs_kmem_cache_alloc(inmem_entry_slab, GFP_NOFS);
 207
 208         /* add atomic page indices to the list */
 209         new->page = page;
 210         INIT_LIST_HEAD(&new->list);
 211
 212         /* increase reference count with clean state */
 213         mutex_lock(&fi->inmem_lock);
 214         get_page(page);
 215         list_add_tail(&new->list, &fi->inmem_pages);
 216         inc_page_count(F2FS_I_SB(inode), F2FS_INMEM_PAGES);
 217         mutex_unlock(&fi->inmem_lock);
 218
 219         trace_f2fs_register_inmem_page(page, INMEM);
 220 }
 221
 222 int commit_inmem_pages(struct inode *inode, bool abort)
 223 {
 224         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 225         struct f2fs_inode_info *fi = F2FS_I(inode);
 226         struct inmem_pages *cur, *tmp;
 227         bool submit_bio = false;
 228         struct f2fs_io_info fio = {
 229                 .sbi = sbi,
 230                 .type = DATA,
 231                 .rw = WRITE_SYNC | REQ_PRIO,
 232                 .encrypted_page = NULL,
 233         };
 234         int err = 0;
 235
 236         /*
 237          * The abort is true only when f2fs_evict_inode is called.
 238          * Basically, the f2fs_evict_inode doesn't produce any data writes, so
 239          * that we don't need to call f2fs_balance_fs.
 240          * Otherwise, f2fs_gc in f2fs_balance_fs can wait forever until this
 241          * inode becomes free by iget_locked in f2fs_iget.
 242          */
 243         if (!abort) {
 244                 f2fs_balance_fs(sbi);
 245                 f2fs_lock_op(sbi);
 246         }
 247
 248         mutex_lock(&fi->inmem_lock);
 249         list_for_each_entry_safe(cur, tmp, &fi->inmem_pages, list) {
 250                 lock_page(cur->page);
 251                 if (!abort) {
 252                         if (cur->page->mapping == inode->i_mapping) {
 253                                 set_page_dirty(cur->page);
 254                                 f2fs_wait_on_page_writeback(cur->page, DATA);
 255                                 if (clear_page_dirty_for_io(cur->page))
 256                                         inode_dec_dirty_pages(inode);
 257                                 trace_f2fs_commit_inmem_page(cur->page, INMEM);
 258                                 fio.page = cur->page;
 259                                 err = do_write_data_page(&fio);
 260                                 submit_bio = true;
 261                                 if (err) {
 262                                         unlock_page(cur->page);
 263                                         break;
 264                                 }
 265                         }
 266                 } else {
 267                         trace_f2fs_commit_inmem_page(cur->page, INMEM_DROP);
 268                 }
 269                 set_page_private(cur->page, 0);
 270                 ClearPagePrivate(cur->page);
 271                 f2fs_put_page(cur->page, 1);
 272
 273                 list_del(&cur->list);
 274                 kmem_cache_free(inmem_entry_slab, cur);
 275                 dec_page_count(F2FS_I_SB(inode), F2FS_INMEM_PAGES);
 276         }
 277         mutex_unlock(&fi->inmem_lock);
 278
 279         if (!abort) {
 280                 f2fs_unlock_op(sbi);
 281                 if (submit_bio)
 282                         f2fs_submit_merged_bio(sbi, DATA, WRITE);
 283         }
 284         return err;
 285 }
 286
 287 /*
 288  * This function balances dirty node and dentry pages.
 289  * In addition, it controls garbage collection.
 290  */
 291 void f2fs_balance_fs(struct f2fs_sb_info *sbi)
 292 {
 293         /*
 294          * We should do GC or end up with checkpoint, if there are so many dirty
 295          * dir/node pages without enough free segments.
 296          */
 297         if (has_not_enough_free_secs(sbi, 0)) {
 298                 mutex_lock(&sbi->gc_mutex);
 299                 f2fs_gc(sbi);
 300         }
 301 }
 302
 303 void f2fs_balance_fs_bg(struct f2fs_sb_info *sbi)
 304 {
 305         /* try to shrink extent cache when there is no enough memory */
 306         if (!available_free_memory(sbi, EXTENT_CACHE))
 307                 f2fs_shrink_extent_tree(sbi, EXTENT_CACHE_SHRINK_NUMBER);
 308
 309         /* check the # of cached NAT entries */
 310         if (!available_free_memory(sbi, NAT_ENTRIES))
 311                 try_to_free_nats(sbi, NAT_ENTRY_PER_BLOCK);
 312
 313         if (!available_free_memory(sbi, FREE_NIDS))
 314                 try_to_free_nids(sbi, NAT_ENTRY_PER_BLOCK * FREE_NID_PAGES);
 315
 316         /* checkpoint is the only way to shrink partial cached entries */
 317         if (!available_free_memory(sbi, NAT_ENTRIES) ||
 318                         excess_prefree_segs(sbi) ||
 319                         !available_free_memory(sbi, INO_ENTRIES))
 320                 f2fs_sync_fs(sbi->sb, true);
 321 }
 322
 323 static int issue_flush_thread(void *data)
 324 {
 325         struct f2fs_sb_info *sbi = data;
 326         struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
 327         wait_queue_head_t *q = &fcc->flush_wait_queue;
 328 repeat:
 329         if (kthread_should_stop())
 330                 return 0;
 331
 332         if (!llist_empty(&fcc->issue_list)) {
 333                 struct bio *bio;
 334                 struct flush_cmd *cmd, *next;
 335                 int ret;
 336
 337                 bio = f2fs_bio_alloc(0);
 338
 339                 fcc->dispatch_list = llist_del_all(&fcc->issue_list);
 340                 fcc->dispatch_list = llist_reverse_order(fcc->dispatch_list);
 341
 342                 bio->bi_bdev = sbi->sb->s_bdev;
 343                 ret = submit_bio_wait(WRITE_FLUSH, bio);
 344
 345                 llist_for_each_entry_safe(cmd, next,
 346                                           fcc->dispatch_list, llnode) {
 347                         cmd->ret = ret;
 348                         complete(&cmd->wait);
 349                 }
 350                 bio_put(bio);
 351                 fcc->dispatch_list = NULL;
 352         }
 353
 354         wait_event_interruptible(*q,
 355                 kthread_should_stop() || !llist_empty(&fcc->issue_list));
 356         goto repeat;
 357 }
 358
 359 int f2fs_issue_flush(struct f2fs_sb_info *sbi)
 360 {
 361         struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
 362         struct flush_cmd cmd;
 363
 364         trace_f2fs_issue_flush(sbi->sb, test_opt(sbi, NOBARRIER),
 365                                         test_opt(sbi, FLUSH_MERGE));
 366
 367         if (test_opt(sbi, NOBARRIER))
 368                 return 0;
 369
 370         if (!test_opt(sbi, FLUSH_MERGE)) {
 371                 struct bio *bio = f2fs_bio_alloc(0);
 372                 int ret;
 373
 374                 bio->bi_bdev = sbi->sb->s_bdev;
 375                 ret = submit_bio_wait(WRITE_FLUSH, bio);
 376                 bio_put(bio);
 377                 return ret;
 378         }
 379
 380         init_completion(&cmd.wait);
 381
 382         llist_add(&cmd.llnode, &fcc->issue_list);
 383
 384         if (!fcc->dispatch_list)
 385                 wake_up(&fcc->flush_wait_queue);
 386
 387         wait_for_completion(&cmd.wait);
 388
 389         return cmd.ret;
 390 }
 391
 392 int create_flush_cmd_control(struct f2fs_sb_info *sbi)
 393 {
 394         dev_t dev = sbi->sb->s_bdev->bd_dev;
 395         struct flush_cmd_control *fcc;
 396         int err = 0;
 397
 398         fcc = kzalloc(sizeof(struct flush_cmd_control), GFP_KERNEL);
 399         if (!fcc)
 400                 return -ENOMEM;
 401         init_waitqueue_head(&fcc->flush_wait_queue);
 402         init_llist_head(&fcc->issue_list);
 403         SM_I(sbi)->cmd_control_info = fcc;
 404         fcc->f2fs_issue_flush = kthread_run(issue_flush_thread, sbi,
 405                                 "f2fs_flush-%u:%u", MAJOR(dev), MINOR(dev));
 406         if (IS_ERR(fcc->f2fs_issue_flush)) {
 407                 err = PTR_ERR(fcc->f2fs_issue_flush);
 408                 kfree(fcc);
 409                 SM_I(sbi)->cmd_control_info = NULL;
 410                 return err;
 411         }
 412
 413         return err;
 414 }
 415
 416 void destroy_flush_cmd_control(struct f2fs_sb_info *sbi)
 417 {
 418         struct flush_cmd_control *fcc = SM_I(sbi)->cmd_control_info;
 419
 420         if (fcc && fcc->f2fs_issue_flush)
 421                 kthread_stop(fcc->f2fs_issue_flush);
 422         kfree(fcc);
 423         SM_I(sbi)->cmd_control_info = NULL;
 424 }
 425
 426 static void __locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
 427                 enum dirty_type dirty_type)
 428 {
 429         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
 430
 431         /* need not be added */
 432         if (IS_CURSEG(sbi, segno))
 433                 return;
 434
 435         if (!test_and_set_bit(segno, dirty_i->dirty_segmap[dirty_type]))
 436                 dirty_i->nr_dirty[dirty_type]++;
 437
 438         if (dirty_type == DIRTY) {
 439                 struct seg_entry *sentry = get_seg_entry(sbi, segno);
 440                 enum dirty_type t = sentry->type;
 441
 442                 if (unlikely(t >= DIRTY)) {
 443                         f2fs_bug_on(sbi, 1);
 444                         return;
 445                 }
 446                 if (!test_and_set_bit(segno, dirty_i->dirty_segmap[t]))
 447                         dirty_i->nr_dirty[t]++;
 448         }
 449 }
 450
 451 static void __remove_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno,
 452                 enum dirty_type dirty_type)
 453 {
 454         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
 455
 456         if (test_and_clear_bit(segno, dirty_i->dirty_segmap[dirty_type]))
 457                 dirty_i->nr_dirty[dirty_type]--;
 458
 459         if (dirty_type == DIRTY) {
 460                 struct seg_entry *sentry = get_seg_entry(sbi, segno);
 461                 enum dirty_type t = sentry->type;
 462
 463                 if (test_and_clear_bit(segno, dirty_i->dirty_segmap[t]))
 464                         dirty_i->nr_dirty[t]--;
 465
 466                 if (get_valid_blocks(sbi, segno, sbi->segs_per_sec) == 0)
 467                         clear_bit(GET_SECNO(sbi, segno),
 468                                                 dirty_i->victim_secmap);
 469         }
 470 }
 471
 472 /*
 473  * Should not occur error such as -ENOMEM.
 474  * Adding dirty entry into seglist is not critical operation.
 475  * If a given segment is one of current working segments, it won't be added.
 476  */
 477 static void locate_dirty_segment(struct f2fs_sb_info *sbi, unsigned int segno)
 478 {
 479         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
 480         unsigned short valid_blocks;
 481
 482         if (segno == NULL_SEGNO || IS_CURSEG(sbi, segno))
 483                 return;
 484
 485         mutex_lock(&dirty_i->seglist_lock);
 486
 487         valid_blocks = get_valid_blocks(sbi, segno, 0);
 488
 489         if (valid_blocks == 0) {
 490                 __locate_dirty_segment(sbi, segno, PRE);
 491                 __remove_dirty_segment(sbi, segno, DIRTY);
 492         } else if (valid_blocks < sbi->blocks_per_seg) {
 493                 __locate_dirty_segment(sbi, segno, DIRTY);
 494         } else {
 495                 /* Recovery routine with SSR needs this */
 496                 __remove_dirty_segment(sbi, segno, DIRTY);
 497         }
 498
 499         mutex_unlock(&dirty_i->seglist_lock);
 500 }
 501
 502 static int f2fs_issue_discard(struct f2fs_sb_info *sbi,
 503                                 block_t blkstart, block_t blklen)
 504 {
 505         sector_t start = SECTOR_FROM_BLOCK(blkstart);
 506         sector_t len = SECTOR_FROM_BLOCK(blklen);
 507         struct seg_entry *se;
 508         unsigned int offset;
 509         block_t i;
 510
 511         for (i = blkstart; i < blkstart + blklen; i++) {
 512                 se = get_seg_entry(sbi, GET_SEGNO(sbi, i));
 513                 offset = GET_BLKOFF_FROM_SEG0(sbi, i);
 514
 515                 if (!f2fs_test_and_set_bit(offset, se->discard_map))
 516                         sbi->discard_blks--;
 517         }
 518         trace_f2fs_issue_discard(sbi->sb, blkstart, blklen);
 519         return blkdev_issue_discard(sbi->sb->s_bdev, start, len, GFP_NOFS, 0);
 520 }
 521
 522 bool discard_next_dnode(struct f2fs_sb_info *sbi, block_t blkaddr)
 523 {
 524         int err = -ENOTSUPP;
 525
 526         if (test_opt(sbi, DISCARD)) {
 527                 struct seg_entry *se = get_seg_entry(sbi,
 528                                 GET_SEGNO(sbi, blkaddr));
 529                 unsigned int offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
 530
 531                 if (f2fs_test_bit(offset, se->discard_map))
 532                         return false;
 533
 534                 err = f2fs_issue_discard(sbi, blkaddr, 1);
 535         }
 536
 537         if (err) {
 538                 update_meta_page(sbi, NULL, blkaddr);
 539                 return true;
 540         }
 541         return false;
 542 }
 543
 544 static void __add_discard_entry(struct f2fs_sb_info *sbi,
 545                 struct cp_control *cpc, struct seg_entry *se,
 546                 unsigned int start, unsigned int end)
 547 {
 548         struct list_head *head = &SM_I(sbi)->discard_list;
 549         struct discard_entry *new, *last;
 550
 551         if (!list_empty(head)) {
 552                 last = list_last_entry(head, struct discard_entry, list);
 553                 if (START_BLOCK(sbi, cpc->trim_start) + start ==
 554                                                 last->blkaddr + last->len) {
 555                         last->len += end - start;
 556                         goto done;
 557                 }
 558         }
 559
 560         new = f2fs_kmem_cache_alloc(discard_entry_slab, GFP_NOFS);
 561         INIT_LIST_HEAD(&new->list);
 562         new->blkaddr = START_BLOCK(sbi, cpc->trim_start) + start;
 563         new->len = end - start;
 564         list_add_tail(&new->list, head);
 565 done:
 566         SM_I(sbi)->nr_discards += end - start;
 567 }
 568
 569 static void add_discard_addrs(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 570 {
 571         int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
 572         int max_blocks = sbi->blocks_per_seg;
 573         struct seg_entry *se = get_seg_entry(sbi, cpc->trim_start);
 574         unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
 575         unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
 576         unsigned long *discard_map = (unsigned long *)se->discard_map;
 577         unsigned long *dmap = SIT_I(sbi)->tmp_map;
 578         unsigned int start = 0, end = -1;
 579         bool force = (cpc->reason == CP_DISCARD);
 580         int i;
 581
 582         if (se->valid_blocks == max_blocks)
 583                 return;
 584
 585         if (!force) {
 586                 if (!test_opt(sbi, DISCARD) || !se->valid_blocks ||
 587                     SM_I(sbi)->nr_discards >= SM_I(sbi)->max_discards)
 588                         return;
 589         }
 590
 591         /* SIT_VBLOCK_MAP_SIZE should be multiple of sizeof(unsigned long) */
 592         for (i = 0; i < entries; i++)
 593                 dmap[i] = force ? ~ckpt_map[i] & ~discard_map[i] :
 594                                 (cur_map[i] ^ ckpt_map[i]) & ckpt_map[i];
 595
 596         while (force || SM_I(sbi)->nr_discards <= SM_I(sbi)->max_discards) {
 597                 start = __find_rev_next_bit(dmap, max_blocks, end + 1);
 598                 if (start >= max_blocks)
 599                         break;
 600
 601                 end = __find_rev_next_zero_bit(dmap, max_blocks, start + 1);
 602                 __add_discard_entry(sbi, cpc, se, start, end);
 603         }
 604 }
 605
 606 void release_discard_addrs(struct f2fs_sb_info *sbi)
 607 {
 608         struct list_head *head = &(SM_I(sbi)->discard_list);
 609         struct discard_entry *entry, *this;
 610
 611         /* drop caches */
 612         list_for_each_entry_safe(entry, this, head, list) {
 613                 list_del(&entry->list);
 614                 kmem_cache_free(discard_entry_slab, entry);
 615         }
 616 }
 617
 618 /*
 619  * Should call clear_prefree_segments after checkpoint is done.
 620  */
 621 static void set_prefree_as_free_segments(struct f2fs_sb_info *sbi)
 622 {
 623         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
 624         unsigned int segno;
 625
 626         mutex_lock(&dirty_i->seglist_lock);
 627         for_each_set_bit(segno, dirty_i->dirty_segmap[PRE], MAIN_SEGS(sbi))
 628                 __set_test_and_free(sbi, segno);
 629         mutex_unlock(&dirty_i->seglist_lock);
 630 }
 631
 632 void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc)
 633 {
 634         struct list_head *head = &(SM_I(sbi)->discard_list);
 635         struct discard_entry *entry, *this;
 636         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
 637         unsigned long *prefree_map = dirty_i->dirty_segmap[PRE];
 638         unsigned int start = 0, end = -1;
 639
 640         mutex_lock(&dirty_i->seglist_lock);
 641
 642         while (1) {
 643                 int i;
 644                 start = find_next_bit(prefree_map, MAIN_SEGS(sbi), end + 1);
 645                 if (start >= MAIN_SEGS(sbi))
 646                         break;
 647                 end = find_next_zero_bit(prefree_map, MAIN_SEGS(sbi),
 648                                                                 start + 1);
 649
 650                 for (i = start; i < end; i++)
 651                         clear_bit(i, prefree_map);
 652
 653                 dirty_i->nr_dirty[PRE] -= end - start;
 654
 655                 if (!test_opt(sbi, DISCARD))
 656                         continue;
 657
 658                 f2fs_issue_discard(sbi, START_BLOCK(sbi, start),
 659                                 (end - start) << sbi->log_blocks_per_seg);
 660         }
 661         mutex_unlock(&dirty_i->seglist_lock);
 662
 663         /* send small discards */
 664         list_for_each_entry_safe(entry, this, head, list) {
 665                 if (cpc->reason == CP_DISCARD && entry->len < cpc->trim_minlen)
 666                         goto skip;
 667                 f2fs_issue_discard(sbi, entry->blkaddr, entry->len);
 668                 cpc->trimmed += entry->len;
 669 skip:
 670                 list_del(&entry->list);
 671                 SM_I(sbi)->nr_discards -= entry->len;
 672                 kmem_cache_free(discard_entry_slab, entry);
 673         }
 674 }
 675
 676 static bool __mark_sit_entry_dirty(struct f2fs_sb_info *sbi, unsigned int segno)
 677 {
 678         struct sit_info *sit_i = SIT_I(sbi);
 679
 680         if (!__test_and_set_bit(segno, sit_i->dirty_sentries_bitmap)) {
 681                 sit_i->dirty_sentries++;
 682                 return false;
 683         }
 684
 685         return true;
 686 }
 687
 688 static void __set_sit_entry_type(struct f2fs_sb_info *sbi, int type,
 689                                         unsigned int segno, int modified)
 690 {
 691         struct seg_entry *se = get_seg_entry(sbi, segno);
 692         se->type = type;
 693         if (modified)
 694                 __mark_sit_entry_dirty(sbi, segno);
 695 }
 696
 697 static void update_sit_entry(struct f2fs_sb_info *sbi, block_t blkaddr, int del)
 698 {
 699         struct seg_entry *se;
 700         unsigned int segno, offset;
 701         long int new_vblocks;
 702
 703         segno = GET_SEGNO(sbi, blkaddr);
 704
 705         se = get_seg_entry(sbi, segno);
 706         new_vblocks = se->valid_blocks + del;
 707         offset = GET_BLKOFF_FROM_SEG0(sbi, blkaddr);
 708
 709         f2fs_bug_on(sbi, (new_vblocks >> (sizeof(unsigned short) << 3) ||
 710                                 (new_vblocks > sbi->blocks_per_seg)));
 711
 712         se->valid_blocks = new_vblocks;
 713         se->mtime = get_mtime(sbi);
 714         SIT_I(sbi)->max_mtime = se->mtime;
 715
 716         /* Update valid block bitmap */
 717         if (del > 0) {
 718                 if (f2fs_test_and_set_bit(offset, se->cur_valid_map))
 719                         f2fs_bug_on(sbi, 1);
 720                 if (!f2fs_test_and_set_bit(offset, se->discard_map))
 721                         sbi->discard_blks--;
 722         } else {
 723                 if (!f2fs_test_and_clear_bit(offset, se->cur_valid_map))
 724                         f2fs_bug_on(sbi, 1);
 725                 if (f2fs_test_and_clear_bit(offset, se->discard_map))
 726                         sbi->discard_blks++;
 727         }
 728         if (!f2fs_test_bit(offset, se->ckpt_valid_map))
 729                 se->ckpt_valid_blocks += del;
 730
 731         __mark_sit_entry_dirty(sbi, segno);
 732
 733         /* update total number of valid blocks to be written in ckpt area */
 734         SIT_I(sbi)->written_valid_blocks += del;
 735
 736         if (sbi->segs_per_sec > 1)
 737                 get_sec_entry(sbi, segno)->valid_blocks += del;
 738 }
 739
 740 void refresh_sit_entry(struct f2fs_sb_info *sbi, block_t old, block_t new)
 741 {
 742         update_sit_entry(sbi, new, 1);
 743         if (GET_SEGNO(sbi, old) != NULL_SEGNO)
 744                 update_sit_entry(sbi, old, -1);
 745
 746         locate_dirty_segment(sbi, GET_SEGNO(sbi, old));
 747         locate_dirty_segment(sbi, GET_SEGNO(sbi, new));
 748 }
 749
 750 void invalidate_blocks(struct f2fs_sb_info *sbi, block_t addr)
 751 {
 752         unsigned int segno = GET_SEGNO(sbi, addr);
 753         struct sit_info *sit_i = SIT_I(sbi);
 754
 755         f2fs_bug_on(sbi, addr == NULL_ADDR);
 756         if (addr == NEW_ADDR)
 757                 return;
 758
 759         /* add it into sit main buffer */
 760         mutex_lock(&sit_i->sentry_lock);
 761
 762         update_sit_entry(sbi, addr, -1);
 763
 764         /* add it into dirty seglist */
 765         locate_dirty_segment(sbi, segno);
 766
 767         mutex_unlock(&sit_i->sentry_lock);
 768 }
 769
 770 /*
 771  * This function should be resided under the curseg_mutex lock
 772  */
 773 static void __add_sum_entry(struct f2fs_sb_info *sbi, int type,
 774                                         struct f2fs_summary *sum)
 775 {
 776         struct curseg_info *curseg = CURSEG_I(sbi, type);
 777         void *addr = curseg->sum_blk;
 778         addr += curseg->next_blkoff * sizeof(struct f2fs_summary);
 779         memcpy(addr, sum, sizeof(struct f2fs_summary));
 780 }
 781
 782 /*
 783  * Calculate the number of current summary pages for writing
 784  */
 785 int npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra)
 786 {
 787         int valid_sum_count = 0;
 788         int i, sum_in_page;
 789
 790         for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
 791                 if (sbi->ckpt->alloc_type[i] == SSR)
 792                         valid_sum_count += sbi->blocks_per_seg;
 793                 else {
 794                         if (for_ra)
 795                                 valid_sum_count += le16_to_cpu(
 796                                         F2FS_CKPT(sbi)->cur_data_blkoff[i]);
 797                         else
 798                                 valid_sum_count += curseg_blkoff(sbi, i);
 799                 }
 800         }
 801
 802         sum_in_page = (PAGE_CACHE_SIZE - 2 * SUM_JOURNAL_SIZE -
 803                         SUM_FOOTER_SIZE) / SUMMARY_SIZE;
 804         if (valid_sum_count <= sum_in_page)
 805                 return 1;
 806         else if ((valid_sum_count - sum_in_page) <=
 807                 (PAGE_CACHE_SIZE - SUM_FOOTER_SIZE) / SUMMARY_SIZE)
 808                 return 2;
 809         return 3;
 810 }
 811
 812 /*
 813  * Caller should put this summary page
 814  */
 815 struct page *get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno)
 816 {
 817         return get_meta_page(sbi, GET_SUM_BLOCK(sbi, segno));
 818 }
 819
 820 void update_meta_page(struct f2fs_sb_info *sbi, void *src, block_t blk_addr)
 821 {
 822         struct page *page = grab_meta_page(sbi, blk_addr);
 823         void *dst = page_address(page);
 824
 825         if (src)
 826                 memcpy(dst, src, PAGE_CACHE_SIZE);
 827         else
 828                 memset(dst, 0, PAGE_CACHE_SIZE);
 829         set_page_dirty(page);
 830         f2fs_put_page(page, 1);
 831 }
 832
 833 static void write_sum_page(struct f2fs_sb_info *sbi,
 834                         struct f2fs_summary_block *sum_blk, block_t blk_addr)
 835 {
 836         update_meta_page(sbi, (void *)sum_blk, blk_addr);
 837 }
 838
 839 static int is_next_segment_free(struct f2fs_sb_info *sbi, int type)
 840 {
 841         struct curseg_info *curseg = CURSEG_I(sbi, type);
 842         unsigned int segno = curseg->segno + 1;
 843         struct free_segmap_info *free_i = FREE_I(sbi);
 844
 845         if (segno < MAIN_SEGS(sbi) && segno % sbi->segs_per_sec)
 846                 return !test_bit(segno, free_i->free_segmap);
 847         return 0;
 848 }
 849
 850 /*
 851  * Find a new segment from the free segments bitmap to right order
 852  * This function should be returned with success, otherwise BUG
 853  */
 854 static void get_new_segment(struct f2fs_sb_info *sbi,
 855                         unsigned int *newseg, bool new_sec, int dir)
 856 {
 857         struct free_segmap_info *free_i = FREE_I(sbi);
 858         unsigned int segno, secno, zoneno;
 859         unsigned int total_zones = MAIN_SECS(sbi) / sbi->secs_per_zone;
 860         unsigned int hint = *newseg / sbi->segs_per_sec;
 861         unsigned int old_zoneno = GET_ZONENO_FROM_SEGNO(sbi, *newseg);
 862         unsigned int left_start = hint;
 863         bool init = true;
 864         int go_left = 0;
 865         int i;
 866
 867         spin_lock(&free_i->segmap_lock);
 868
 869         if (!new_sec && ((*newseg + 1) % sbi->segs_per_sec)) {
 870                 segno = find_next_zero_bit(free_i->free_segmap,
 871                                         MAIN_SEGS(sbi), *newseg + 1);
 872                 if (segno - *newseg < sbi->segs_per_sec -
 873                                         (*newseg % sbi->segs_per_sec))
 874                         goto got_it;
 875         }
 876 find_other_zone:
 877         secno = find_next_zero_bit(free_i->free_secmap, MAIN_SECS(sbi), hint);
 878         if (secno >= MAIN_SECS(sbi)) {
 879                 if (dir == ALLOC_RIGHT) {
 880                         secno = find_next_zero_bit(free_i->free_secmap,
 881                                                         MAIN_SECS(sbi), 0);
 882                         f2fs_bug_on(sbi, secno >= MAIN_SECS(sbi));
 883                 } else {
 884                         go_left = 1;
 885                         left_start = hint - 1;
 886                 }
 887         }
 888         if (go_left == 0)
 889                 goto skip_left;
 890
 891         while (test_bit(left_start, free_i->free_secmap)) {
 892                 if (left_start > 0) {
 893                         left_start--;
 894                         continue;
 895                 }
 896                 left_start = find_next_zero_bit(free_i->free_secmap,
 897                                                         MAIN_SECS(sbi), 0);
 898                 f2fs_bug_on(sbi, left_start >= MAIN_SECS(sbi));
 899                 break;
 900         }
 901         secno = left_start;
 902 skip_left:
 903         hint = secno;
 904         segno = secno * sbi->segs_per_sec;
 905         zoneno = secno / sbi->secs_per_zone;
 906
 907         /* give up on finding another zone */
 908         if (!init)
 909                 goto got_it;
 910         if (sbi->secs_per_zone == 1)
 911                 goto got_it;
 912         if (zoneno == old_zoneno)
 913                 goto got_it;
 914         if (dir == ALLOC_LEFT) {
 915                 if (!go_left && zoneno + 1 >= total_zones)
 916                         goto got_it;
 917                 if (go_left && zoneno == 0)
 918                         goto got_it;
 919         }
 920         for (i = 0; i < NR_CURSEG_TYPE; i++)
 921                 if (CURSEG_I(sbi, i)->zone == zoneno)
 922                         break;
 923
 924         if (i < NR_CURSEG_TYPE) {
 925                 /* zone is in user, try another */
 926                 if (go_left)
 927                         hint = zoneno * sbi->secs_per_zone - 1;
 928                 else if (zoneno + 1 >= total_zones)
 929                         hint = 0;
 930                 else
 931                         hint = (zoneno + 1) * sbi->secs_per_zone;
 932                 init = false;
 933                 goto find_other_zone;
 934         }
 935 got_it:
 936         /* set it as dirty segment in free segmap */
 937         f2fs_bug_on(sbi, test_bit(segno, free_i->free_segmap));
 938         __set_inuse(sbi, segno);
 939         *newseg = segno;
 940         spin_unlock(&free_i->segmap_lock);
 941 }
 942
 943 static void reset_curseg(struct f2fs_sb_info *sbi, int type, int modified)
 944 {
 945         struct curseg_info *curseg = CURSEG_I(sbi, type);
 946         struct summary_footer *sum_footer;
 947
 948         curseg->segno = curseg->next_segno;
 949         curseg->zone = GET_ZONENO_FROM_SEGNO(sbi, curseg->segno);
 950         curseg->next_blkoff = 0;
 951         curseg->next_segno = NULL_SEGNO;
 952
 953         sum_footer = &(curseg->sum_blk->footer);
 954         memset(sum_footer, 0, sizeof(struct summary_footer));
 955         if (IS_DATASEG(type))
 956                 SET_SUM_TYPE(sum_footer, SUM_TYPE_DATA);
 957         if (IS_NODESEG(type))
 958                 SET_SUM_TYPE(sum_footer, SUM_TYPE_NODE);
 959         __set_sit_entry_type(sbi, type, curseg->segno, modified);
 960 }
 961
 962 /*
 963  * Allocate a current working segment.
 964  * This function always allocates a free segment in LFS manner.
 965  */
 966 static void new_curseg(struct f2fs_sb_info *sbi, int type, bool new_sec)
 967 {
 968         struct curseg_info *curseg = CURSEG_I(sbi, type);
 969         unsigned int segno = curseg->segno;
 970         int dir = ALLOC_LEFT;
 971
 972         write_sum_page(sbi, curseg->sum_blk,
 973                                 GET_SUM_BLOCK(sbi, segno));
 974         if (type == CURSEG_WARM_DATA || type == CURSEG_COLD_DATA)
 975                 dir = ALLOC_RIGHT;
 976
 977         if (test_opt(sbi, NOHEAP))
 978                 dir = ALLOC_RIGHT;
 979
 980         get_new_segment(sbi, &segno, new_sec, dir);
 981         curseg->next_segno = segno;
 982         reset_curseg(sbi, type, 1);
 983         curseg->alloc_type = LFS;
 984 }
 985
 986 static void __next_free_blkoff(struct f2fs_sb_info *sbi,
 987                         struct curseg_info *seg, block_t start)
 988 {
 989         struct seg_entry *se = get_seg_entry(sbi, seg->segno);
 990         int entries = SIT_VBLOCK_MAP_SIZE / sizeof(unsigned long);
 991         unsigned long *target_map = SIT_I(sbi)->tmp_map;
 992         unsigned long *ckpt_map = (unsigned long *)se->ckpt_valid_map;
 993         unsigned long *cur_map = (unsigned long *)se->cur_valid_map;
 994         int i, pos;
 995
 996         for (i = 0; i < entries; i++)
 997                 target_map[i] = ckpt_map[i] | cur_map[i];
 998
 999         pos = __find_rev_next_zero_bit(target_map, sbi->blocks_per_seg, start);
1000
1001         seg->next_blkoff = pos;
1002 }
1003
1004 /*
1005  * If a segment is written by LFS manner, next block offset is just obtained
1006  * by increasing the current block offset. However, if a segment is written by
1007  * SSR manner, next block offset obtained by calling __next_free_blkoff
1008  */
1009 static void __refresh_next_blkoff(struct f2fs_sb_info *sbi,
1010                                 struct curseg_info *seg)
1011 {
1012         if (seg->alloc_type == SSR)
1013                 __next_free_blkoff(sbi, seg, seg->next_blkoff + 1);
1014         else
1015                 seg->next_blkoff++;
1016 }
1017
1018 /*
1019  * This function always allocates a used segment(from dirty seglist) by SSR
1020  * manner, so it should recover the existing segment information of valid blocks
1021  */
1022 static void change_curseg(struct f2fs_sb_info *sbi, int type, bool reuse)
1023 {
1024         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
1025         struct curseg_info *curseg = CURSEG_I(sbi, type);
1026         unsigned int new_segno = curseg->next_segno;
1027         struct f2fs_summary_block *sum_node;
1028         struct page *sum_page;
1029
1030         write_sum_page(sbi, curseg->sum_blk,
1031                                 GET_SUM_BLOCK(sbi, curseg->segno));
1032         __set_test_and_inuse(sbi, new_segno);
1033
1034         mutex_lock(&dirty_i->seglist_lock);
1035         __remove_dirty_segment(sbi, new_segno, PRE);
1036         __remove_dirty_segment(sbi, new_segno, DIRTY);
1037         mutex_unlock(&dirty_i->seglist_lock);
1038
1039         reset_curseg(sbi, type, 1);
1040         curseg->alloc_type = SSR;
1041         __next_free_blkoff(sbi, curseg, 0);
1042
1043         if (reuse) {
1044                 sum_page = get_sum_page(sbi, new_segno);
1045                 sum_node = (struct f2fs_summary_block *)page_address(sum_page);
1046                 memcpy(curseg->sum_blk, sum_node, SUM_ENTRY_SIZE);
1047                 f2fs_put_page(sum_page, 1);
1048         }
1049 }
1050
1051 static int get_ssr_segment(struct f2fs_sb_info *sbi, int type)
1052 {
1053         struct curseg_info *curseg = CURSEG_I(sbi, type);
1054         const struct victim_selection *v_ops = DIRTY_I(sbi)->v_ops;
1055
1056         if (IS_NODESEG(type) || !has_not_enough_free_secs(sbi, 0))
1057                 return v_ops->get_victim(sbi,
1058                                 &(curseg)->next_segno, BG_GC, type, SSR);
1059
1060         /* For data segments, let's do SSR more intensively */
1061         for (; type >= CURSEG_HOT_DATA; type--)
1062                 if (v_ops->get_victim(sbi, &(curseg)->next_segno,
1063                                                 BG_GC, type, SSR))
1064                         return 1;
1065         return 0;
1066 }
1067
1068 /*
1069  * flush out current segment and replace it with new segment
1070  * This function should be returned with success, otherwise BUG
1071  */
1072 static void allocate_segment_by_default(struct f2fs_sb_info *sbi,
1073                                                 int type, bool force)
1074 {
1075         struct curseg_info *curseg = CURSEG_I(sbi, type);
1076
1077         if (force)
1078                 new_curseg(sbi, type, true);
1079         else if (type == CURSEG_WARM_NODE)
1080                 new_curseg(sbi, type, false);
1081         else if (curseg->alloc_type == LFS && is_next_segment_free(sbi, type))
1082                 new_curseg(sbi, type, false);
1083         else if (need_SSR(sbi) && get_ssr_segment(sbi, type))
1084                 change_curseg(sbi, type, true);
1085         else
1086                 new_curseg(sbi, type, false);
1087
1088         stat_inc_seg_type(sbi, curseg);
1089 }
1090
1091 static void __allocate_new_segments(struct f2fs_sb_info *sbi, int type)
1092 {
1093         struct curseg_info *curseg = CURSEG_I(sbi, type);
1094         unsigned int old_segno;
1095
1096         old_segno = curseg->segno;
1097         SIT_I(sbi)->s_ops->allocate_segment(sbi, type, true);
1098         locate_dirty_segment(sbi, old_segno);
1099 }
1100
1101 void allocate_new_segments(struct f2fs_sb_info *sbi)
1102 {
1103         int i;
1104
1105         for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++)
1106                 __allocate_new_segments(sbi, i);
1107 }
1108
1109 static const struct segment_allocation default_salloc_ops = {
1110         .allocate_segment = allocate_segment_by_default,
1111 };
1112
1113 int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
1114 {
1115         __u64 start = F2FS_BYTES_TO_BLK(range->start);
1116         __u64 end = start + F2FS_BYTES_TO_BLK(range->len) - 1;
1117         unsigned int start_segno, end_segno;
1118         struct cp_control cpc;
1119
1120         if (start >= MAX_BLKADDR(sbi) || range->len < sbi->blocksize)
1121                 return -EINVAL;
1122
1123         cpc.trimmed = 0;
1124         if (end <= MAIN_BLKADDR(sbi))
1125                 goto out;
1126
1127         /* start/end segment number in main_area */
1128         start_segno = (start <= MAIN_BLKADDR(sbi)) ? 0 : GET_SEGNO(sbi, start);
1129         end_segno = (end >= MAX_BLKADDR(sbi)) ? MAIN_SEGS(sbi) - 1 :
1130                                                 GET_SEGNO(sbi, end);
1131         cpc.reason = CP_DISCARD;
1132         cpc.trim_minlen = max_t(__u64, 1, F2FS_BYTES_TO_BLK(range->minlen));
1133
1134         /* do checkpoint to issue discard commands safely */
1135         for (; start_segno <= end_segno; start_segno = cpc.trim_end + 1) {
1136                 cpc.trim_start = start_segno;
1137
1138                 if (sbi->discard_blks == 0)
1139                         break;
1140                 else if (sbi->discard_blks < BATCHED_TRIM_BLOCKS(sbi))
1141                         cpc.trim_end = end_segno;
1142                 else
1143                         cpc.trim_end = min_t(unsigned int,
1144                                 rounddown(start_segno +
1145                                 BATCHED_TRIM_SEGMENTS(sbi),
1146                                 sbi->segs_per_sec) - 1, end_segno);
1147
1148                 mutex_lock(&sbi->gc_mutex);
1149                 write_checkpoint(sbi, &cpc);
1150                 mutex_unlock(&sbi->gc_mutex);
1151         }
1152 out:
1153         range->len = F2FS_BLK_TO_BYTES(cpc.trimmed);
1154         return 0;
1155 }
1156
1157 static bool __has_curseg_space(struct f2fs_sb_info *sbi, int type)
1158 {
1159         struct curseg_info *curseg = CURSEG_I(sbi, type);
1160         if (curseg->next_blkoff < sbi->blocks_per_seg)
1161                 return true;
1162         return false;
1163 }
1164
1165 static int __get_segment_type_2(struct page *page, enum page_type p_type)
1166 {
1167         if (p_type == DATA)
1168                 return CURSEG_HOT_DATA;
1169         else
1170                 return CURSEG_HOT_NODE;
1171 }
1172
1173 static int __get_segment_type_4(struct page *page, enum page_type p_type)
1174 {
1175         if (p_type == DATA) {
1176                 struct inode *inode = page->mapping->host;
1177
1178                 if (S_ISDIR(inode->i_mode))
1179                         return CURSEG_HOT_DATA;
1180                 else
1181                         return CURSEG_COLD_DATA;
1182         } else {
1183                 if (IS_DNODE(page) && is_cold_node(page))
1184                         return CURSEG_WARM_NODE;
1185                 else
1186                         return CURSEG_COLD_NODE;
1187         }
1188 }
1189
1190 static int __get_segment_type_6(struct page *page, enum page_type p_type)
1191 {
1192         if (p_type == DATA) {
1193                 struct inode *inode = page->mapping->host;
1194
1195                 if (S_ISDIR(inode->i_mode))
1196                         return CURSEG_HOT_DATA;
1197                 else if (is_cold_data(page) || file_is_cold(inode))
1198                         return CURSEG_COLD_DATA;
1199                 else
1200                         return CURSEG_WARM_DATA;
1201         } else {
1202                 if (IS_DNODE(page))
1203                         return is_cold_node(page) ? CURSEG_WARM_NODE :
1204                                                 CURSEG_HOT_NODE;
1205                 else
1206                         return CURSEG_COLD_NODE;
1207         }
1208 }
1209
1210 static int __get_segment_type(struct page *page, enum page_type p_type)
1211 {
1212         switch (F2FS_P_SB(page)->active_logs) {
1213         case 2:
1214                 return __get_segment_type_2(page, p_type);
1215         case 4:
1216                 return __get_segment_type_4(page, p_type);
1217         }
1218         /* NR_CURSEG_TYPE(6) logs by default */
1219         f2fs_bug_on(F2FS_P_SB(page),
1220                 F2FS_P_SB(page)->active_logs != NR_CURSEG_TYPE);
1221         return __get_segment_type_6(page, p_type);
1222 }
1223
1224 void allocate_data_block(struct f2fs_sb_info *sbi, struct page *page,
1225                 block_t old_blkaddr, block_t *new_blkaddr,
1226                 struct f2fs_summary *sum, int type)
1227 {
1228         struct sit_info *sit_i = SIT_I(sbi);
1229         struct curseg_info *curseg;
1230         bool direct_io = (type == CURSEG_DIRECT_IO);
1231
1232         type = direct_io ? CURSEG_WARM_DATA : type;
1233
1234         curseg = CURSEG_I(sbi, type);
1235
1236         mutex_lock(&curseg->curseg_mutex);
1237         mutex_lock(&sit_i->sentry_lock);
1238
1239         /* direct_io'ed data is aligned to the segment for better performance */
1240         if (direct_io && curseg->next_blkoff &&
1241                                 !has_not_enough_free_secs(sbi, 0))
1242                 __allocate_new_segments(sbi, type);
1243
1244         *new_blkaddr = NEXT_FREE_BLKADDR(sbi, curseg);
1245
1246         /*
1247          * __add_sum_entry should be resided under the curseg_mutex
1248          * because, this function updates a summary entry in the
1249          * current summary block.
1250          */
1251         __add_sum_entry(sbi, type, sum);
1252
1253         __refresh_next_blkoff(sbi, curseg);
1254
1255         stat_inc_block_count(sbi, curseg);
1256
1257         if (!__has_curseg_space(sbi, type))
1258                 sit_i->s_ops->allocate_segment(sbi, type, false);
1259         /*
1260          * SIT information should be updated before segment allocation,
1261          * since SSR needs latest valid block information.
1262          */
1263         refresh_sit_entry(sbi, old_blkaddr, *new_blkaddr);
1264
1265         mutex_unlock(&sit_i->sentry_lock);
1266
1267         if (page && IS_NODESEG(type))
1268                 fill_node_footer_blkaddr(page, NEXT_FREE_BLKADDR(sbi, curseg));
1269
1270         mutex_unlock(&curseg->curseg_mutex);
1271 }
1272
1273 static void do_write_page(struct f2fs_summary *sum, struct f2fs_io_info *fio)
1274 {
1275         int type = __get_segment_type(fio->page, fio->type);
1276
1277         allocate_data_block(fio->sbi, fio->page, fio->blk_addr,
1278                                         &fio->blk_addr, sum, type);
1279
1280         /* writeout dirty page into bdev */
1281         f2fs_submit_page_mbio(fio);
1282 }
1283
1284 void write_meta_page(struct f2fs_sb_info *sbi, struct page *page)
1285 {
1286         struct f2fs_io_info fio = {
1287                 .sbi = sbi,
1288                 .type = META,
1289                 .rw = WRITE_SYNC | REQ_META | REQ_PRIO,
1290                 .blk_addr = page->index,
1291                 .page = page,
1292                 .encrypted_page = NULL,
1293         };
1294
1295         set_page_writeback(page);
1296         f2fs_submit_page_mbio(&fio);
1297 }
1298
1299 void write_node_page(unsigned int nid, struct f2fs_io_info *fio)
1300 {
1301         struct f2fs_summary sum;
1302
1303         set_summary(&sum, nid, 0, 0);
1304         do_write_page(&sum, fio);
1305 }
1306
1307 void write_data_page(struct dnode_of_data *dn, struct f2fs_io_info *fio)
1308 {
1309         struct f2fs_sb_info *sbi = fio->sbi;
1310         struct f2fs_summary sum;
1311         struct node_info ni;
1312
1313         f2fs_bug_on(sbi, dn->data_blkaddr == NULL_ADDR);
1314         get_node_info(sbi, dn->nid, &ni);
1315         set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
1316         do_write_page(&sum, fio);
1317         dn->data_blkaddr = fio->blk_addr;
1318 }
1319
1320 void rewrite_data_page(struct f2fs_io_info *fio)
1321 {
1322         stat_inc_inplace_blocks(fio->sbi);
1323         f2fs_submit_page_mbio(fio);
1324 }
1325
1326 static void __f2fs_replace_block(struct f2fs_sb_info *sbi,
1327                                 struct f2fs_summary *sum,
1328                                 block_t old_blkaddr, block_t new_blkaddr,
1329                                 bool recover_curseg)
1330 {
1331         struct sit_info *sit_i = SIT_I(sbi);
1332         struct curseg_info *curseg;
1333         unsigned int segno, old_cursegno;
1334         struct seg_entry *se;
1335         int type;
1336         unsigned short old_blkoff;
1337
1338         segno = GET_SEGNO(sbi, new_blkaddr);
1339         se = get_seg_entry(sbi, segno);
1340         type = se->type;
1341
1342         if (!recover_curseg) {
1343                 /* for recovery flow */
1344                 if (se->valid_blocks == 0 && !IS_CURSEG(sbi, segno)) {
1345                         if (old_blkaddr == NULL_ADDR)
1346                                 type = CURSEG_COLD_DATA;
1347                         else
1348                                 type = CURSEG_WARM_DATA;
1349                 }
1350         } else {
1351                 if (!IS_CURSEG(sbi, segno))
1352                         type = CURSEG_WARM_DATA;
1353         }
1354
1355         curseg = CURSEG_I(sbi, type);
1356
1357         mutex_lock(&curseg->curseg_mutex);
1358         mutex_lock(&sit_i->sentry_lock);
1359
1360         old_cursegno = curseg->segno;
1361         old_blkoff = curseg->next_blkoff;
1362
1363         /* change the current segment */
1364         if (segno != curseg->segno) {
1365                 curseg->next_segno = segno;
1366                 change_curseg(sbi, type, true);
1367         }
1368
1369         curseg->next_blkoff = GET_BLKOFF_FROM_SEG0(sbi, new_blkaddr);
1370         __add_sum_entry(sbi, type, sum);
1371
1372         refresh_sit_entry(sbi, old_blkaddr, new_blkaddr);
1373         locate_dirty_segment(sbi, old_cursegno);
1374
1375         if (recover_curseg) {
1376                 if (old_cursegno != curseg->segno) {
1377                         curseg->next_segno = old_cursegno;
1378                         change_curseg(sbi, type, true);
1379                 }
1380                 curseg->next_blkoff = old_blkoff;
1381         }
1382
1383         mutex_unlock(&sit_i->sentry_lock);
1384         mutex_unlock(&curseg->curseg_mutex);
1385 }
1386
1387 void f2fs_replace_block(struct f2fs_sb_info *sbi, struct dnode_of_data *dn,
1388                                 block_t old_addr, block_t new_addr,
1389                                 unsigned char version, bool recover_curseg)
1390 {
1391         struct f2fs_summary sum;
1392
1393         set_summary(&sum, dn->nid, dn->ofs_in_node, version);
1394
1395         __f2fs_replace_block(sbi, &sum, old_addr, new_addr, recover_curseg);
1396
1397         dn->data_blkaddr = new_addr;
1398         set_data_blkaddr(dn);
1399         f2fs_update_extent_cache(dn);
1400 }
1401
1402 static inline bool is_merged_page(struct f2fs_sb_info *sbi,
1403                                         struct page *page, enum page_type type)
1404 {
1405         enum page_type btype = PAGE_TYPE_OF_BIO(type);
1406         struct f2fs_bio_info *io = &sbi->write_io[btype];
1407         struct bio_vec *bvec;
1408         struct page *target;
1409         int i;
1410
1411         down_read(&io->io_rwsem);
1412         if (!io->bio) {
1413                 up_read(&io->io_rwsem);
1414                 return false;
1415         }
1416
1417         bio_for_each_segment_all(bvec, io->bio, i) {
1418
1419                 if (bvec->bv_page->mapping) {
1420                         target = bvec->bv_page;
1421                 } else {
1422                         struct f2fs_crypto_ctx *ctx;
1423
1424                         /* encrypted page */
1425                         ctx = (struct f2fs_crypto_ctx *)page_private(
1426                                                                 bvec->bv_page);
1427                         target = ctx->w.control_page;
1428                 }
1429
1430                 if (page == target) {
1431                         up_read(&io->io_rwsem);
1432                         return true;
1433                 }
1434         }
1435
1436         up_read(&io->io_rwsem);
1437         return false;
1438 }
1439
1440 void f2fs_wait_on_page_writeback(struct page *page,
1441                                 enum page_type type)
1442 {
1443         if (PageWriteback(page)) {
1444                 struct f2fs_sb_info *sbi = F2FS_P_SB(page);
1445
1446                 if (is_merged_page(sbi, page, type))
1447                         f2fs_submit_merged_bio(sbi, type, WRITE);
1448                 wait_on_page_writeback(page);
1449         }
1450 }
1451
1452 static int read_compacted_summaries(struct f2fs_sb_info *sbi)
1453 {
1454         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1455         struct curseg_info *seg_i;
1456         unsigned char *kaddr;
1457         struct page *page;
1458         block_t start;
1459         int i, j, offset;
1460
1461         start = start_sum_block(sbi);
1462
1463         page = get_meta_page(sbi, start++);
1464         kaddr = (unsigned char *)page_address(page);
1465
1466         /* Step 1: restore nat cache */
1467         seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
1468         memcpy(&seg_i->sum_blk->n_nats, kaddr, SUM_JOURNAL_SIZE);
1469
1470         /* Step 2: restore sit cache */
1471         seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
1472         memcpy(&seg_i->sum_blk->n_sits, kaddr + SUM_JOURNAL_SIZE,
1473                                                 SUM_JOURNAL_SIZE);
1474         offset = 2 * SUM_JOURNAL_SIZE;
1475
1476         /* Step 3: restore summary entries */
1477         for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1478                 unsigned short blk_off;
1479                 unsigned int segno;
1480
1481                 seg_i = CURSEG_I(sbi, i);
1482                 segno = le32_to_cpu(ckpt->cur_data_segno[i]);
1483                 blk_off = le16_to_cpu(ckpt->cur_data_blkoff[i]);
1484                 seg_i->next_segno = segno;
1485                 reset_curseg(sbi, i, 0);
1486                 seg_i->alloc_type = ckpt->alloc_type[i];
1487                 seg_i->next_blkoff = blk_off;
1488
1489                 if (seg_i->alloc_type == SSR)
1490                         blk_off = sbi->blocks_per_seg;
1491
1492                 for (j = 0; j < blk_off; j++) {
1493                         struct f2fs_summary *s;
1494                         s = (struct f2fs_summary *)(kaddr + offset);
1495                         seg_i->sum_blk->entries[j] = *s;
1496                         offset += SUMMARY_SIZE;
1497                         if (offset + SUMMARY_SIZE <= PAGE_CACHE_SIZE -
1498                                                 SUM_FOOTER_SIZE)
1499                                 continue;
1500
1501                         f2fs_put_page(page, 1);
1502                         page = NULL;
1503
1504                         page = get_meta_page(sbi, start++);
1505                         kaddr = (unsigned char *)page_address(page);
1506                         offset = 0;
1507                 }
1508         }
1509         f2fs_put_page(page, 1);
1510         return 0;
1511 }
1512
1513 static int read_normal_summaries(struct f2fs_sb_info *sbi, int type)
1514 {
1515         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1516         struct f2fs_summary_block *sum;
1517         struct curseg_info *curseg;
1518         struct page *new;
1519         unsigned short blk_off;
1520         unsigned int segno = 0;
1521         block_t blk_addr = 0;
1522
1523         /* get segment number and block addr */
1524         if (IS_DATASEG(type)) {
1525                 segno = le32_to_cpu(ckpt->cur_data_segno[type]);
1526                 blk_off = le16_to_cpu(ckpt->cur_data_blkoff[type -
1527                                                         CURSEG_HOT_DATA]);
1528                 if (__exist_node_summaries(sbi))
1529                         blk_addr = sum_blk_addr(sbi, NR_CURSEG_TYPE, type);
1530                 else
1531                         blk_addr = sum_blk_addr(sbi, NR_CURSEG_DATA_TYPE, type);
1532         } else {
1533                 segno = le32_to_cpu(ckpt->cur_node_segno[type -
1534                                                         CURSEG_HOT_NODE]);
1535                 blk_off = le16_to_cpu(ckpt->cur_node_blkoff[type -
1536                                                         CURSEG_HOT_NODE]);
1537                 if (__exist_node_summaries(sbi))
1538                         blk_addr = sum_blk_addr(sbi, NR_CURSEG_NODE_TYPE,
1539                                                         type - CURSEG_HOT_NODE);
1540                 else
1541                         blk_addr = GET_SUM_BLOCK(sbi, segno);
1542         }
1543
1544         new = get_meta_page(sbi, blk_addr);
1545         sum = (struct f2fs_summary_block *)page_address(new);
1546
1547         if (IS_NODESEG(type)) {
1548                 if (__exist_node_summaries(sbi)) {
1549                         struct f2fs_summary *ns = &sum->entries[0];
1550                         int i;
1551                         for (i = 0; i < sbi->blocks_per_seg; i++, ns++) {
1552                                 ns->version = 0;
1553                                 ns->ofs_in_node = 0;
1554                         }
1555                 } else {
1556                         int err;
1557
1558                         err = restore_node_summary(sbi, segno, sum);
1559                         if (err) {
1560                                 f2fs_put_page(new, 1);
1561                                 return err;
1562                         }
1563                 }
1564         }
1565
1566         /* set uncompleted segment to curseg */
1567         curseg = CURSEG_I(sbi, type);
1568         mutex_lock(&curseg->curseg_mutex);
1569         memcpy(curseg->sum_blk, sum, PAGE_CACHE_SIZE);
1570         curseg->next_segno = segno;
1571         reset_curseg(sbi, type, 0);
1572         curseg->alloc_type = ckpt->alloc_type[type];
1573         curseg->next_blkoff = blk_off;
1574         mutex_unlock(&curseg->curseg_mutex);
1575         f2fs_put_page(new, 1);
1576         return 0;
1577 }
1578
1579 static int restore_curseg_summaries(struct f2fs_sb_info *sbi)
1580 {
1581         int type = CURSEG_HOT_DATA;
1582         int err;
1583
1584         if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_COMPACT_SUM_FLAG)) {
1585                 int npages = npages_for_summary_flush(sbi, true);
1586
1587                 if (npages >= 2)
1588                         ra_meta_pages(sbi, start_sum_block(sbi), npages,
1589                                                                 META_CP);
1590
1591                 /* restore for compacted data summary */
1592                 if (read_compacted_summaries(sbi))
1593                         return -EINVAL;
1594                 type = CURSEG_HOT_NODE;
1595         }
1596
1597         if (__exist_node_summaries(sbi))
1598                 ra_meta_pages(sbi, sum_blk_addr(sbi, NR_CURSEG_TYPE, type),
1599                                         NR_CURSEG_TYPE - type, META_CP);
1600
1601         for (; type <= CURSEG_COLD_NODE; type++) {
1602                 err = read_normal_summaries(sbi, type);
1603                 if (err)
1604                         return err;
1605         }
1606
1607         return 0;
1608 }
1609
1610 static void write_compacted_summaries(struct f2fs_sb_info *sbi, block_t blkaddr)
1611 {
1612         struct page *page;
1613         unsigned char *kaddr;
1614         struct f2fs_summary *summary;
1615         struct curseg_info *seg_i;
1616         int written_size = 0;
1617         int i, j;
1618
1619         page = grab_meta_page(sbi, blkaddr++);
1620         kaddr = (unsigned char *)page_address(page);
1621
1622         /* Step 1: write nat cache */
1623         seg_i = CURSEG_I(sbi, CURSEG_HOT_DATA);
1624         memcpy(kaddr, &seg_i->sum_blk->n_nats, SUM_JOURNAL_SIZE);
1625         written_size += SUM_JOURNAL_SIZE;
1626
1627         /* Step 2: write sit cache */
1628         seg_i = CURSEG_I(sbi, CURSEG_COLD_DATA);
1629         memcpy(kaddr + written_size, &seg_i->sum_blk->n_sits,
1630                                                 SUM_JOURNAL_SIZE);
1631         written_size += SUM_JOURNAL_SIZE;
1632
1633         /* Step 3: write summary entries */
1634         for (i = CURSEG_HOT_DATA; i <= CURSEG_COLD_DATA; i++) {
1635                 unsigned short blkoff;
1636                 seg_i = CURSEG_I(sbi, i);
1637                 if (sbi->ckpt->alloc_type[i] == SSR)
1638                         blkoff = sbi->blocks_per_seg;
1639                 else
1640                         blkoff = curseg_blkoff(sbi, i);
1641
1642                 for (j = 0; j < blkoff; j++) {
1643                         if (!page) {
1644                                 page = grab_meta_page(sbi, blkaddr++);
1645                                 kaddr = (unsigned char *)page_address(page);
1646                                 written_size = 0;
1647                         }
1648                         summary = (struct f2fs_summary *)(kaddr + written_size);
1649                         *summary = seg_i->sum_blk->entries[j];
1650                         written_size += SUMMARY_SIZE;
1651
1652                         if (written_size + SUMMARY_SIZE <= PAGE_CACHE_SIZE -
1653                                                         SUM_FOOTER_SIZE)
1654                                 continue;
1655
1656                         set_page_dirty(page);
1657                         f2fs_put_page(page, 1);
1658                         page = NULL;
1659                 }
1660         }
1661         if (page) {
1662                 set_page_dirty(page);
1663                 f2fs_put_page(page, 1);
1664         }
1665 }
1666
1667 static void write_normal_summaries(struct f2fs_sb_info *sbi,
1668                                         block_t blkaddr, int type)
1669 {
1670         int i, end;
1671         if (IS_DATASEG(type))
1672                 end = type + NR_CURSEG_DATA_TYPE;
1673         else
1674                 end = type + NR_CURSEG_NODE_TYPE;
1675
1676         for (i = type; i < end; i++) {
1677                 struct curseg_info *sum = CURSEG_I(sbi, i);
1678                 mutex_lock(&sum->curseg_mutex);
1679                 write_sum_page(sbi, sum->sum_blk, blkaddr + (i - type));
1680                 mutex_unlock(&sum->curseg_mutex);
1681         }
1682 }
1683
1684 void write_data_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
1685 {
1686         if (is_set_ckpt_flags(F2FS_CKPT(sbi), CP_COMPACT_SUM_FLAG))
1687                 write_compacted_summaries(sbi, start_blk);
1688         else
1689                 write_normal_summaries(sbi, start_blk, CURSEG_HOT_DATA);
1690 }
1691
1692 void write_node_summaries(struct f2fs_sb_info *sbi, block_t start_blk)
1693 {
1694         write_normal_summaries(sbi, start_blk, CURSEG_HOT_NODE);
1695 }
1696
1697 int lookup_journal_in_cursum(struct f2fs_summary_block *sum, int type,
1698                                         unsigned int val, int alloc)
1699 {
1700         int i;
1701
1702         if (type == NAT_JOURNAL) {
1703                 for (i = 0; i < nats_in_cursum(sum); i++) {
1704                         if (le32_to_cpu(nid_in_journal(sum, i)) == val)
1705                                 return i;
1706                 }
1707                 if (alloc && nats_in_cursum(sum) < NAT_JOURNAL_ENTRIES)
1708                         return update_nats_in_cursum(sum, 1);
1709         } else if (type == SIT_JOURNAL) {
1710                 for (i = 0; i < sits_in_cursum(sum); i++)
1711                         if (le32_to_cpu(segno_in_journal(sum, i)) == val)
1712                                 return i;
1713                 if (alloc && sits_in_cursum(sum) < SIT_JOURNAL_ENTRIES)
1714                         return update_sits_in_cursum(sum, 1);
1715         }
1716         return -1;
1717 }
1718
1719 static struct page *get_current_sit_page(struct f2fs_sb_info *sbi,
1720                                         unsigned int segno)
1721 {
1722         return get_meta_page(sbi, current_sit_addr(sbi, segno));
1723 }
1724
1725 static struct page *get_next_sit_page(struct f2fs_sb_info *sbi,
1726                                         unsigned int start)
1727 {
1728         struct sit_info *sit_i = SIT_I(sbi);
1729         struct page *src_page, *dst_page;
1730         pgoff_t src_off, dst_off;
1731         void *src_addr, *dst_addr;
1732
1733         src_off = current_sit_addr(sbi, start);
1734         dst_off = next_sit_addr(sbi, src_off);
1735
1736         /* get current sit block page without lock */
1737         src_page = get_meta_page(sbi, src_off);
1738         dst_page = grab_meta_page(sbi, dst_off);
1739         f2fs_bug_on(sbi, PageDirty(src_page));
1740
1741         src_addr = page_address(src_page);
1742         dst_addr = page_address(dst_page);
1743         memcpy(dst_addr, src_addr, PAGE_CACHE_SIZE);
1744
1745         set_page_dirty(dst_page);
1746         f2fs_put_page(src_page, 1);
1747
1748         set_to_next_sit(sit_i, start);
1749
1750         return dst_page;
1751 }
1752
1753 static struct sit_entry_set *grab_sit_entry_set(void)
1754 {
1755         struct sit_entry_set *ses =
1756                         f2fs_kmem_cache_alloc(sit_entry_set_slab, GFP_NOFS);
1757
1758         ses->entry_cnt = 0;
1759         INIT_LIST_HEAD(&ses->set_list);
1760         return ses;
1761 }
1762
1763 static void release_sit_entry_set(struct sit_entry_set *ses)
1764 {
1765         list_del(&ses->set_list);
1766         kmem_cache_free(sit_entry_set_slab, ses);
1767 }
1768
1769 static void adjust_sit_entry_set(struct sit_entry_set *ses,
1770                                                 struct list_head *head)
1771 {
1772         struct sit_entry_set *next = ses;
1773
1774         if (list_is_last(&ses->set_list, head))
1775                 return;
1776
1777         list_for_each_entry_continue(next, head, set_list)
1778                 if (ses->entry_cnt <= next->entry_cnt)
1779                         break;
1780
1781         list_move_tail(&ses->set_list, &next->set_list);
1782 }
1783
1784 static void add_sit_entry(unsigned int segno, struct list_head *head)
1785 {
1786         struct sit_entry_set *ses;
1787         unsigned int start_segno = START_SEGNO(segno);
1788
1789         list_for_each_entry(ses, head, set_list) {
1790                 if (ses->start_segno == start_segno) {
1791                         ses->entry_cnt++;
1792                         adjust_sit_entry_set(ses, head);
1793                         return;
1794                 }
1795         }
1796
1797         ses = grab_sit_entry_set();
1798
1799         ses->start_segno = start_segno;
1800         ses->entry_cnt++;
1801         list_add(&ses->set_list, head);
1802 }
1803
1804 static void add_sits_in_set(struct f2fs_sb_info *sbi)
1805 {
1806         struct f2fs_sm_info *sm_info = SM_I(sbi);
1807         struct list_head *set_list = &sm_info->sit_entry_set;
1808         unsigned long *bitmap = SIT_I(sbi)->dirty_sentries_bitmap;
1809         unsigned int segno;
1810
1811         for_each_set_bit(segno, bitmap, MAIN_SEGS(sbi))
1812                 add_sit_entry(segno, set_list);
1813 }
1814
1815 static void remove_sits_in_journal(struct f2fs_sb_info *sbi)
1816 {
1817         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
1818         struct f2fs_summary_block *sum = curseg->sum_blk;
1819         int i;
1820
1821         for (i = sits_in_cursum(sum) - 1; i >= 0; i--) {
1822                 unsigned int segno;
1823                 bool dirtied;
1824
1825                 segno = le32_to_cpu(segno_in_journal(sum, i));
1826                 dirtied = __mark_sit_entry_dirty(sbi, segno);
1827
1828                 if (!dirtied)
1829                         add_sit_entry(segno, &SM_I(sbi)->sit_entry_set);
1830         }
1831         update_sits_in_cursum(sum, -sits_in_cursum(sum));
1832 }
1833
1834 /*
1835  * CP calls this function, which flushes SIT entries including sit_journal,
1836  * and moves prefree segs to free segs.
1837  */
1838 void flush_sit_entries(struct f2fs_sb_info *sbi, struct cp_control *cpc)
1839 {
1840         struct sit_info *sit_i = SIT_I(sbi);
1841         unsigned long *bitmap = sit_i->dirty_sentries_bitmap;
1842         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
1843         struct f2fs_summary_block *sum = curseg->sum_blk;
1844         struct sit_entry_set *ses, *tmp;
1845         struct list_head *head = &SM_I(sbi)->sit_entry_set;
1846         bool to_journal = true;
1847         struct seg_entry *se;
1848
1849         mutex_lock(&curseg->curseg_mutex);
1850         mutex_lock(&sit_i->sentry_lock);
1851
1852         if (!sit_i->dirty_sentries)
1853                 goto out;
1854
1855         /*
1856          * add and account sit entries of dirty bitmap in sit entry
1857          * set temporarily
1858          */
1859         add_sits_in_set(sbi);
1860
1861         /*
1862          * if there are no enough space in journal to store dirty sit
1863          * entries, remove all entries from journal and add and account
1864          * them in sit entry set.
1865          */
1866         if (!__has_cursum_space(sum, sit_i->dirty_sentries, SIT_JOURNAL))
1867                 remove_sits_in_journal(sbi);
1868
1869         /*
1870          * there are two steps to flush sit entries:
1871          * #1, flush sit entries to journal in current cold data summary block.
1872          * #2, flush sit entries to sit page.
1873          */
1874         list_for_each_entry_safe(ses, tmp, head, set_list) {
1875                 struct page *page = NULL;
1876                 struct f2fs_sit_block *raw_sit = NULL;
1877                 unsigned int start_segno = ses->start_segno;
1878                 unsigned int end = min(start_segno + SIT_ENTRY_PER_BLOCK,
1879                                                 (unsigned long)MAIN_SEGS(sbi));
1880                 unsigned int segno = start_segno;
1881
1882                 if (to_journal &&
1883                         !__has_cursum_space(sum, ses->entry_cnt, SIT_JOURNAL))
1884                         to_journal = false;
1885
1886                 if (!to_journal) {
1887                         page = get_next_sit_page(sbi, start_segno);
1888                         raw_sit = page_address(page);
1889                 }
1890
1891                 /* flush dirty sit entries in region of current sit set */
1892                 for_each_set_bit_from(segno, bitmap, end) {
1893                         int offset, sit_offset;
1894
1895                         se = get_seg_entry(sbi, segno);
1896
1897                         /* add discard candidates */
1898                         if (cpc->reason != CP_DISCARD) {
1899                                 cpc->trim_start = segno;
1900                                 add_discard_addrs(sbi, cpc);
1901                         }
1902
1903                         if (to_journal) {
1904                                 offset = lookup_journal_in_cursum(sum,
1905                                                         SIT_JOURNAL, segno, 1);
1906                                 f2fs_bug_on(sbi, offset < 0);
1907                                 segno_in_journal(sum, offset) =
1908                                                         cpu_to_le32(segno);
1909                                 seg_info_to_raw_sit(se,
1910                                                 &sit_in_journal(sum, offset));
1911                         } else {
1912                                 sit_offset = SIT_ENTRY_OFFSET(sit_i, segno);
1913                                 seg_info_to_raw_sit(se,
1914                                                 &raw_sit->entries[sit_offset]);
1915                         }
1916
1917                         __clear_bit(segno, bitmap);
1918                         sit_i->dirty_sentries--;
1919                         ses->entry_cnt--;
1920                 }
1921
1922                 if (!to_journal)
1923                         f2fs_put_page(page, 1);
1924
1925                 f2fs_bug_on(sbi, ses->entry_cnt);
1926                 release_sit_entry_set(ses);
1927         }
1928
1929         f2fs_bug_on(sbi, !list_empty(head));
1930         f2fs_bug_on(sbi, sit_i->dirty_sentries);
1931 out:
1932         if (cpc->reason == CP_DISCARD) {
1933                 for (; cpc->trim_start <= cpc->trim_end; cpc->trim_start++)
1934                         add_discard_addrs(sbi, cpc);
1935         }
1936         mutex_unlock(&sit_i->sentry_lock);
1937         mutex_unlock(&curseg->curseg_mutex);
1938
1939         set_prefree_as_free_segments(sbi);
1940 }
1941
1942 static int build_sit_info(struct f2fs_sb_info *sbi)
1943 {
1944         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
1945         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
1946         struct sit_info *sit_i;
1947         unsigned int sit_segs, start;
1948         char *src_bitmap, *dst_bitmap;
1949         unsigned int bitmap_size;
1950
1951         /* allocate memory for SIT information */
1952         sit_i = kzalloc(sizeof(struct sit_info), GFP_KERNEL);
1953         if (!sit_i)
1954                 return -ENOMEM;
1955
1956         SM_I(sbi)->sit_info = sit_i;
1957
1958         sit_i->sentries = vzalloc(MAIN_SEGS(sbi) * sizeof(struct seg_entry));
1959         if (!sit_i->sentries)
1960                 return -ENOMEM;
1961
1962         bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
1963         sit_i->dirty_sentries_bitmap = kzalloc(bitmap_size, GFP_KERNEL);
1964         if (!sit_i->dirty_sentries_bitmap)
1965                 return -ENOMEM;
1966
1967         for (start = 0; start < MAIN_SEGS(sbi); start++) {
1968                 sit_i->sentries[start].cur_valid_map
1969                         = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
1970                 sit_i->sentries[start].ckpt_valid_map
1971                         = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
1972                 sit_i->sentries[start].discard_map
1973                         = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
1974                 if (!sit_i->sentries[start].cur_valid_map ||
1975                                 !sit_i->sentries[start].ckpt_valid_map ||
1976                                 !sit_i->sentries[start].discard_map)
1977                         return -ENOMEM;
1978         }
1979
1980         sit_i->tmp_map = kzalloc(SIT_VBLOCK_MAP_SIZE, GFP_KERNEL);
1981         if (!sit_i->tmp_map)
1982                 return -ENOMEM;
1983
1984         if (sbi->segs_per_sec > 1) {
1985                 sit_i->sec_entries = vzalloc(MAIN_SECS(sbi) *
1986                                         sizeof(struct sec_entry));
1987                 if (!sit_i->sec_entries)
1988                         return -ENOMEM;
1989         }
1990
1991         /* get information related with SIT */
1992         sit_segs = le32_to_cpu(raw_super->segment_count_sit) >> 1;
1993
1994         /* setup SIT bitmap from ckeckpoint pack */
1995         bitmap_size = __bitmap_size(sbi, SIT_BITMAP);
1996         src_bitmap = __bitmap_ptr(sbi, SIT_BITMAP);
1997
1998         dst_bitmap = kmemdup(src_bitmap, bitmap_size, GFP_KERNEL);
1999         if (!dst_bitmap)
2000                 return -ENOMEM;
2001
2002         /* init SIT information */
2003         sit_i->s_ops = &default_salloc_ops;
2004
2005         sit_i->sit_base_addr = le32_to_cpu(raw_super->sit_blkaddr);
2006         sit_i->sit_blocks = sit_segs << sbi->log_blocks_per_seg;
2007         sit_i->written_valid_blocks = le64_to_cpu(ckpt->valid_block_count);
2008         sit_i->sit_bitmap = dst_bitmap;
2009         sit_i->bitmap_size = bitmap_size;
2010         sit_i->dirty_sentries = 0;
2011         sit_i->sents_per_block = SIT_ENTRY_PER_BLOCK;
2012         sit_i->elapsed_time = le64_to_cpu(sbi->ckpt->elapsed_time);
2013         sit_i->mounted_time = CURRENT_TIME_SEC.tv_sec;
2014         mutex_init(&sit_i->sentry_lock);
2015         return 0;
2016 }
2017
2018 static int build_free_segmap(struct f2fs_sb_info *sbi)
2019 {
2020         struct free_segmap_info *free_i;
2021         unsigned int bitmap_size, sec_bitmap_size;
2022
2023         /* allocate memory for free segmap information */
2024         free_i = kzalloc(sizeof(struct free_segmap_info), GFP_KERNEL);
2025         if (!free_i)
2026                 return -ENOMEM;
2027
2028         SM_I(sbi)->free_info = free_i;
2029
2030         bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
2031         free_i->free_segmap = kmalloc(bitmap_size, GFP_KERNEL);
2032         if (!free_i->free_segmap)
2033                 return -ENOMEM;
2034
2035         sec_bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
2036         free_i->free_secmap = kmalloc(sec_bitmap_size, GFP_KERNEL);
2037         if (!free_i->free_secmap)
2038                 return -ENOMEM;
2039
2040         /* set all segments as dirty temporarily */
2041         memset(free_i->free_segmap, 0xff, bitmap_size);
2042         memset(free_i->free_secmap, 0xff, sec_bitmap_size);
2043
2044         /* init free segmap information */
2045         free_i->start_segno = GET_SEGNO_FROM_SEG0(sbi, MAIN_BLKADDR(sbi));
2046         free_i->free_segments = 0;
2047         free_i->free_sections = 0;
2048         spin_lock_init(&free_i->segmap_lock);
2049         return 0;
2050 }
2051
2052 static int build_curseg(struct f2fs_sb_info *sbi)
2053 {
2054         struct curseg_info *array;
2055         int i;
2056
2057         array = kcalloc(NR_CURSEG_TYPE, sizeof(*array), GFP_KERNEL);
2058         if (!array)
2059                 return -ENOMEM;
2060
2061         SM_I(sbi)->curseg_array = array;
2062
2063         for (i = 0; i < NR_CURSEG_TYPE; i++) {
2064                 mutex_init(&array[i].curseg_mutex);
2065                 array[i].sum_blk = kzalloc(PAGE_CACHE_SIZE, GFP_KERNEL);
2066                 if (!array[i].sum_blk)
2067                         return -ENOMEM;
2068                 array[i].segno = NULL_SEGNO;
2069                 array[i].next_blkoff = 0;
2070         }
2071         return restore_curseg_summaries(sbi);
2072 }
2073
2074 static void build_sit_entries(struct f2fs_sb_info *sbi)
2075 {
2076         struct sit_info *sit_i = SIT_I(sbi);
2077         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_COLD_DATA);
2078         struct f2fs_summary_block *sum = curseg->sum_blk;
2079         int sit_blk_cnt = SIT_BLK_CNT(sbi);
2080         unsigned int i, start, end;
2081         unsigned int readed, start_blk = 0;
2082         int nrpages = MAX_BIO_BLOCKS(sbi);
2083
2084         do {
2085                 readed = ra_meta_pages(sbi, start_blk, nrpages, META_SIT);
2086
2087                 start = start_blk * sit_i->sents_per_block;
2088                 end = (start_blk + readed) * sit_i->sents_per_block;
2089
2090                 for (; start < end && start < MAIN_SEGS(sbi); start++) {
2091                         struct seg_entry *se = &sit_i->sentries[start];
2092                         struct f2fs_sit_block *sit_blk;
2093                         struct f2fs_sit_entry sit;
2094                         struct page *page;
2095
2096                         mutex_lock(&curseg->curseg_mutex);
2097                         for (i = 0; i < sits_in_cursum(sum); i++) {
2098                                 if (le32_to_cpu(segno_in_journal(sum, i))
2099                                                                 == start) {
2100                                         sit = sit_in_journal(sum, i);
2101                                         mutex_unlock(&curseg->curseg_mutex);
2102                                         goto got_it;
2103                                 }
2104                         }
2105                         mutex_unlock(&curseg->curseg_mutex);
2106
2107                         page = get_current_sit_page(sbi, start);
2108                         sit_blk = (struct f2fs_sit_block *)page_address(page);
2109                         sit = sit_blk->entries[SIT_ENTRY_OFFSET(sit_i, start)];
2110                         f2fs_put_page(page, 1);
2111 got_it:
2112                         check_block_count(sbi, start, &sit);
2113                         seg_info_from_raw_sit(se, &sit);
2114
2115                         /* build discard map only one time */
2116                         memcpy(se->discard_map, se->cur_valid_map, SIT_VBLOCK_MAP_SIZE);
2117                         sbi->discard_blks += sbi->blocks_per_seg - se->valid_blocks;
2118
2119                         if (sbi->segs_per_sec > 1) {
2120                                 struct sec_entry *e = get_sec_entry(sbi, start);
2121                                 e->valid_blocks += se->valid_blocks;
2122                         }
2123                 }
2124                 start_blk += readed;
2125         } while (start_blk < sit_blk_cnt);
2126 }
2127
2128 static void init_free_segmap(struct f2fs_sb_info *sbi)
2129 {
2130         unsigned int start;
2131         int type;
2132
2133         for (start = 0; start < MAIN_SEGS(sbi); start++) {
2134                 struct seg_entry *sentry = get_seg_entry(sbi, start);
2135                 if (!sentry->valid_blocks)
2136                         __set_free(sbi, start);
2137         }
2138
2139         /* set use the current segments */
2140         for (type = CURSEG_HOT_DATA; type <= CURSEG_COLD_NODE; type++) {
2141                 struct curseg_info *curseg_t = CURSEG_I(sbi, type);
2142                 __set_test_and_inuse(sbi, curseg_t->segno);
2143         }
2144 }
2145
2146 static void init_dirty_segmap(struct f2fs_sb_info *sbi)
2147 {
2148         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2149         struct free_segmap_info *free_i = FREE_I(sbi);
2150         unsigned int segno = 0, offset = 0;
2151         unsigned short valid_blocks;
2152
2153         while (1) {
2154                 /* find dirty segment based on free segmap */
2155                 segno = find_next_inuse(free_i, MAIN_SEGS(sbi), offset);
2156                 if (segno >= MAIN_SEGS(sbi))
2157                         break;
2158                 offset = segno + 1;
2159                 valid_blocks = get_valid_blocks(sbi, segno, 0);
2160                 if (valid_blocks == sbi->blocks_per_seg || !valid_blocks)
2161                         continue;
2162                 if (valid_blocks > sbi->blocks_per_seg) {
2163                         f2fs_bug_on(sbi, 1);
2164                         continue;
2165                 }
2166                 mutex_lock(&dirty_i->seglist_lock);
2167                 __locate_dirty_segment(sbi, segno, DIRTY);
2168                 mutex_unlock(&dirty_i->seglist_lock);
2169         }
2170 }
2171
2172 static int init_victim_secmap(struct f2fs_sb_info *sbi)
2173 {
2174         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2175         unsigned int bitmap_size = f2fs_bitmap_size(MAIN_SECS(sbi));
2176
2177         dirty_i->victim_secmap = kzalloc(bitmap_size, GFP_KERNEL);
2178         if (!dirty_i->victim_secmap)
2179                 return -ENOMEM;
2180         return 0;
2181 }
2182
2183 static int build_dirty_segmap(struct f2fs_sb_info *sbi)
2184 {
2185         struct dirty_seglist_info *dirty_i;
2186         unsigned int bitmap_size, i;
2187
2188         /* allocate memory for dirty segments list information */
2189         dirty_i = kzalloc(sizeof(struct dirty_seglist_info), GFP_KERNEL);
2190         if (!dirty_i)
2191                 return -ENOMEM;
2192
2193         SM_I(sbi)->dirty_info = dirty_i;
2194         mutex_init(&dirty_i->seglist_lock);
2195
2196         bitmap_size = f2fs_bitmap_size(MAIN_SEGS(sbi));
2197
2198         for (i = 0; i < NR_DIRTY_TYPE; i++) {
2199                 dirty_i->dirty_segmap[i] = kzalloc(bitmap_size, GFP_KERNEL);
2200                 if (!dirty_i->dirty_segmap[i])
2201                         return -ENOMEM;
2202         }
2203
2204         init_dirty_segmap(sbi);
2205         return init_victim_secmap(sbi);
2206 }
2207
2208 /*
2209  * Update min, max modified time for cost-benefit GC algorithm
2210  */
2211 static void init_min_max_mtime(struct f2fs_sb_info *sbi)
2212 {
2213         struct sit_info *sit_i = SIT_I(sbi);
2214         unsigned int segno;
2215
2216         mutex_lock(&sit_i->sentry_lock);
2217
2218         sit_i->min_mtime = LLONG_MAX;
2219
2220         for (segno = 0; segno < MAIN_SEGS(sbi); segno += sbi->segs_per_sec) {
2221                 unsigned int i;
2222                 unsigned long long mtime = 0;
2223
2224                 for (i = 0; i < sbi->segs_per_sec; i++)
2225                         mtime += get_seg_entry(sbi, segno + i)->mtime;
2226
2227                 mtime = div_u64(mtime, sbi->segs_per_sec);
2228
2229                 if (sit_i->min_mtime > mtime)
2230                         sit_i->min_mtime = mtime;
2231         }
2232         sit_i->max_mtime = get_mtime(sbi);
2233         mutex_unlock(&sit_i->sentry_lock);
2234 }
2235
2236 int build_segment_manager(struct f2fs_sb_info *sbi)
2237 {
2238         struct f2fs_super_block *raw_super = F2FS_RAW_SUPER(sbi);
2239         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
2240         struct f2fs_sm_info *sm_info;
2241         int err;
2242
2243         sm_info = kzalloc(sizeof(struct f2fs_sm_info), GFP_KERNEL);
2244         if (!sm_info)
2245                 return -ENOMEM;
2246
2247         /* init sm info */
2248         sbi->sm_info = sm_info;
2249         sm_info->seg0_blkaddr = le32_to_cpu(raw_super->segment0_blkaddr);
2250         sm_info->main_blkaddr = le32_to_cpu(raw_super->main_blkaddr);
2251         sm_info->segment_count = le32_to_cpu(raw_super->segment_count);
2252         sm_info->reserved_segments = le32_to_cpu(ckpt->rsvd_segment_count);
2253         sm_info->ovp_segments = le32_to_cpu(ckpt->overprov_segment_count);
2254         sm_info->main_segments = le32_to_cpu(raw_super->segment_count_main);
2255         sm_info->ssa_blkaddr = le32_to_cpu(raw_super->ssa_blkaddr);
2256         sm_info->rec_prefree_segments = sm_info->main_segments *
2257                                         DEF_RECLAIM_PREFREE_SEGMENTS / 100;
2258         sm_info->ipu_policy = 1 << F2FS_IPU_FSYNC;
2259         sm_info->min_ipu_util = DEF_MIN_IPU_UTIL;
2260         sm_info->min_fsync_blocks = DEF_MIN_FSYNC_BLOCKS;
2261
2262         INIT_LIST_HEAD(&sm_info->discard_list);
2263         sm_info->nr_discards = 0;
2264         sm_info->max_discards = 0;
2265
2266         sm_info->trim_sections = DEF_BATCHED_TRIM_SECTIONS;
2267
2268         INIT_LIST_HEAD(&sm_info->sit_entry_set);
2269
2270         if (test_opt(sbi, FLUSH_MERGE) && !f2fs_readonly(sbi->sb)) {
2271                 err = create_flush_cmd_control(sbi);
2272                 if (err)
2273                         return err;
2274         }
2275
2276         err = build_sit_info(sbi);
2277         if (err)
2278                 return err;
2279         err = build_free_segmap(sbi);
2280         if (err)
2281                 return err;
2282         err = build_curseg(sbi);
2283         if (err)
2284                 return err;
2285
2286         /* reinit free segmap based on SIT */
2287         build_sit_entries(sbi);
2288
2289         init_free_segmap(sbi);
2290         err = build_dirty_segmap(sbi);
2291         if (err)
2292                 return err;
2293
2294         init_min_max_mtime(sbi);
2295         return 0;
2296 }
2297
2298 static void discard_dirty_segmap(struct f2fs_sb_info *sbi,
2299                 enum dirty_type dirty_type)
2300 {
2301         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2302
2303         mutex_lock(&dirty_i->seglist_lock);
2304         kfree(dirty_i->dirty_segmap[dirty_type]);
2305         dirty_i->nr_dirty[dirty_type] = 0;
2306         mutex_unlock(&dirty_i->seglist_lock);
2307 }
2308
2309 static void destroy_victim_secmap(struct f2fs_sb_info *sbi)
2310 {
2311         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2312         kfree(dirty_i->victim_secmap);
2313 }
2314
2315 static void destroy_dirty_segmap(struct f2fs_sb_info *sbi)
2316 {
2317         struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
2318         int i;
2319
2320         if (!dirty_i)
2321                 return;
2322
2323         /* discard pre-free/dirty segments list */
2324         for (i = 0; i < NR_DIRTY_TYPE; i++)
2325                 discard_dirty_segmap(sbi, i);
2326
2327         destroy_victim_secmap(sbi);
2328         SM_I(sbi)->dirty_info = NULL;
2329         kfree(dirty_i);
2330 }
2331
2332 static void destroy_curseg(struct f2fs_sb_info *sbi)
2333 {
2334         struct curseg_info *array = SM_I(sbi)->curseg_array;
2335         int i;
2336
2337         if (!array)
2338                 return;
2339         SM_I(sbi)->curseg_array = NULL;
2340         for (i = 0; i < NR_CURSEG_TYPE; i++)
2341                 kfree(array[i].sum_blk);
2342         kfree(array);
2343 }
2344
2345 static void destroy_free_segmap(struct f2fs_sb_info *sbi)
2346 {
2347         struct free_segmap_info *free_i = SM_I(sbi)->free_info;
2348         if (!free_i)
2349                 return;
2350         SM_I(sbi)->free_info = NULL;
2351         kfree(free_i->free_segmap);
2352         kfree(free_i->free_secmap);
2353         kfree(free_i);
2354 }
2355
2356 static void destroy_sit_info(struct f2fs_sb_info *sbi)
2357 {
2358         struct sit_info *sit_i = SIT_I(sbi);
2359         unsigned int start;
2360
2361         if (!sit_i)
2362                 return;
2363
2364         if (sit_i->sentries) {
2365                 for (start = 0; start < MAIN_SEGS(sbi); start++) {
2366                         kfree(sit_i->sentries[start].cur_valid_map);
2367                         kfree(sit_i->sentries[start].ckpt_valid_map);
2368                         kfree(sit_i->sentries[start].discard_map);
2369                 }
2370         }
2371         kfree(sit_i->tmp_map);
2372
2373         vfree(sit_i->sentries);
2374         vfree(sit_i->sec_entries);
2375         kfree(sit_i->dirty_sentries_bitmap);
2376
2377         SM_I(sbi)->sit_info = NULL;
2378         kfree(sit_i->sit_bitmap);
2379         kfree(sit_i);
2380 }
2381
2382 void destroy_segment_manager(struct f2fs_sb_info *sbi)
2383 {
2384         struct f2fs_sm_info *sm_info = SM_I(sbi);
2385
2386         if (!sm_info)
2387                 return;
2388         destroy_flush_cmd_control(sbi);
2389         destroy_dirty_segmap(sbi);
2390         destroy_curseg(sbi);
2391         destroy_free_segmap(sbi);
2392         destroy_sit_info(sbi);
2393         sbi->sm_info = NULL;
2394         kfree(sm_info);
2395 }
2396
2397 int __init create_segment_manager_caches(void)
2398 {
2399         discard_entry_slab = f2fs_kmem_cache_create("discard_entry",
2400                         sizeof(struct discard_entry));
2401         if (!discard_entry_slab)
2402                 goto fail;
2403
2404         sit_entry_set_slab = f2fs_kmem_cache_create("sit_entry_set",
2405                         sizeof(struct sit_entry_set));
2406         if (!sit_entry_set_slab)
2407                 goto destory_discard_entry;
2408
2409         inmem_entry_slab = f2fs_kmem_cache_create("inmem_page_entry",
2410                         sizeof(struct inmem_pages));
2411         if (!inmem_entry_slab)
2412                 goto destroy_sit_entry_set;
2413         return 0;
2414
2415 destroy_sit_entry_set:
2416         kmem_cache_destroy(sit_entry_set_slab);
2417 destory_discard_entry:
2418         kmem_cache_destroy(discard_entry_slab);
2419 fail:
2420         return -ENOMEM;
2421 }
2422
2423 void destroy_segment_manager_caches(void)
2424 {
2425         kmem_cache_destroy(sit_entry_set_slab);
2426         kmem_cache_destroy(discard_entry_slab);
2427         kmem_cache_destroy(inmem_entry_slab);
2428 }