fs/f2fs/extent_cache.c

   1 /*
   2  * f2fs extent cache support
   3  *
   4  * Copyright (c) 2015 Motorola Mobility
   5  * Copyright (c) 2015 Samsung Electronics
   6  * Authors: Jaegeuk Kim <jaegeuk@kernel.org>
   7  *          Chao Yu <chao2.yu@samsung.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/fs.h>
  15 #include <linux/f2fs_fs.h>
  16
  17 #include "f2fs.h"
  18 #include "node.h"
  19 #include <trace/events/f2fs.h>
  20
  21 static struct rb_entry *__lookup_rb_tree_fast(struct rb_entry *cached_re,
  22                                                         unsigned int ofs)
  23 {
  24         if (cached_re) {
  25                 if (cached_re->ofs <= ofs &&
  26                                 cached_re->ofs + cached_re->len > ofs) {
  27                         return cached_re;
  28                 }
  29         }
  30         return NULL;
  31 }
  32
  33 static struct rb_entry *__lookup_rb_tree_slow(struct rb_root *root,
  34                                                         unsigned int ofs)
  35 {
  36         struct rb_node *node = root->rb_node;
  37         struct rb_entry *re;
  38
  39         while (node) {
  40                 re = rb_entry(node, struct rb_entry, rb_node);
  41
  42                 if (ofs < re->ofs)
  43                         node = node->rb_left;
  44                 else if (ofs >= re->ofs + re->len)
  45                         node = node->rb_right;
  46                 else
  47                         return re;
  48         }
  49         return NULL;
  50 }
  51
  52 struct rb_entry *__lookup_rb_tree(struct rb_root *root,
  53                                 struct rb_entry *cached_re, unsigned int ofs)
  54 {
  55         struct rb_entry *re;
  56
  57         re = __lookup_rb_tree_fast(cached_re, ofs);
  58         if (!re)
  59                 return __lookup_rb_tree_slow(root, ofs);
  60
  61         return re;
  62 }
  63
  64 struct rb_node **__lookup_rb_tree_for_insert(struct f2fs_sb_info *sbi,
  65                                 struct rb_root *root, struct rb_node **parent,
  66                                 unsigned int ofs)
  67 {
  68         struct rb_node **p = &root->rb_node;
  69         struct rb_entry *re;
  70
  71         while (*p) {
  72                 *parent = *p;
  73                 re = rb_entry(*parent, struct rb_entry, rb_node);
  74
  75                 if (ofs < re->ofs)
  76                         p = &(*p)->rb_left;
  77                 else if (ofs >= re->ofs + re->len)
  78                         p = &(*p)->rb_right;
  79                 else
  80                         f2fs_bug_on(sbi, 1);
  81         }
  82
  83         return p;
  84 }
  85
  86 /*
  87  * lookup rb entry in position of @ofs in rb-tree,
  88  * if hit, return the entry, otherwise, return NULL
  89  * @prev_ex: extent before ofs
  90  * @next_ex: extent after ofs
  91  * @insert_p: insert point for new extent at ofs
  92  * in order to simpfy the insertion after.
  93  * tree must stay unchanged between lookup and insertion.
  94  */
  95 struct rb_entry *__lookup_rb_tree_ret(struct rb_root *root,
  96                                 struct rb_entry *cached_re,
  97                                 unsigned int ofs,
  98                                 struct rb_entry **prev_entry,
  99                                 struct rb_entry **next_entry,
 100                                 struct rb_node ***insert_p,
 101                                 struct rb_node **insert_parent,
 102                                 bool force)
 103 {
 104         struct rb_node **pnode = &root->rb_node;
 105         struct rb_node *parent = NULL, *tmp_node;
 106         struct rb_entry *re = cached_re;
 107
 108         *insert_p = NULL;
 109         *insert_parent = NULL;
 110         *prev_entry = NULL;
 111         *next_entry = NULL;
 112
 113         if (RB_EMPTY_ROOT(root))
 114                 return NULL;
 115
 116         if (re) {
 117                 if (re->ofs <= ofs && re->ofs + re->len > ofs)
 118                         goto lookup_neighbors;
 119         }
 120
 121         while (*pnode) {
 122                 parent = *pnode;
 123                 re = rb_entry(*pnode, struct rb_entry, rb_node);
 124
 125                 if (ofs < re->ofs)
 126                         pnode = &(*pnode)->rb_left;
 127                 else if (ofs >= re->ofs + re->len)
 128                         pnode = &(*pnode)->rb_right;
 129                 else
 130                         goto lookup_neighbors;
 131         }
 132
 133         *insert_p = pnode;
 134         *insert_parent = parent;
 135
 136         re = rb_entry(parent, struct rb_entry, rb_node);
 137         tmp_node = parent;
 138         if (parent && ofs > re->ofs)
 139                 tmp_node = rb_next(parent);
 140         *next_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
 141
 142         tmp_node = parent;
 143         if (parent && ofs < re->ofs)
 144                 tmp_node = rb_prev(parent);
 145         *prev_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
 146         return NULL;
 147
 148 lookup_neighbors:
 149         if (ofs == re->ofs || force) {
 150                 /* lookup prev node for merging backward later */
 151                 tmp_node = rb_prev(&re->rb_node);
 152                 *prev_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
 153         }
 154         if (ofs == re->ofs + re->len - 1 || force) {
 155                 /* lookup next node for merging frontward later */
 156                 tmp_node = rb_next(&re->rb_node);
 157                 *next_entry = rb_entry_safe(tmp_node, struct rb_entry, rb_node);
 158         }
 159         return re;
 160 }
 161
 162 bool __check_rb_tree_consistence(struct f2fs_sb_info *sbi,
 163                                                 struct rb_root *root)
 164 {
 165 #ifdef CONFIG_F2FS_CHECK_FS
 166         struct rb_node *cur = rb_first(root), *next;
 167         struct rb_entry *cur_re, *next_re;
 168
 169         if (!cur)
 170                 return true;
 171
 172         while (cur) {
 173                 next = rb_next(cur);
 174                 if (!next)
 175                         return true;
 176
 177                 cur_re = rb_entry(cur, struct rb_entry, rb_node);
 178                 next_re = rb_entry(next, struct rb_entry, rb_node);
 179
 180                 if (cur_re->ofs + cur_re->len > next_re->ofs) {
 181                         f2fs_msg(sbi->sb, KERN_INFO, "inconsistent rbtree, "
 182                                 "cur(%u, %u) next(%u, %u)",
 183                                 cur_re->ofs, cur_re->len,
 184                                 next_re->ofs, next_re->len);
 185                         return false;
 186                 }
 187
 188                 cur = next;
 189         }
 190 #endif
 191         return true;
 192 }
 193
 194 static struct kmem_cache *extent_tree_slab;
 195 static struct kmem_cache *extent_node_slab;
 196
 197 static struct extent_node *__attach_extent_node(struct f2fs_sb_info *sbi,
 198                                 struct extent_tree *et, struct extent_info *ei,
 199                                 struct rb_node *parent, struct rb_node **p)
 200 {
 201         struct extent_node *en;
 202
 203         en = kmem_cache_alloc(extent_node_slab, GFP_ATOMIC);
 204         if (!en)
 205                 return NULL;
 206
 207         en->ei = *ei;
 208         INIT_LIST_HEAD(&en->list);
 209         en->et = et;
 210
 211         rb_link_node(&en->rb_node, parent, p);
 212         rb_insert_color(&en->rb_node, &et->root);
 213         atomic_inc(&et->node_cnt);
 214         atomic_inc(&sbi->total_ext_node);
 215         return en;
 216 }
 217
 218 static void __detach_extent_node(struct f2fs_sb_info *sbi,
 219                                 struct extent_tree *et, struct extent_node *en)
 220 {
 221         rb_erase(&en->rb_node, &et->root);
 222         atomic_dec(&et->node_cnt);
 223         atomic_dec(&sbi->total_ext_node);
 224
 225         if (et->cached_en == en)
 226                 et->cached_en = NULL;
 227         kmem_cache_free(extent_node_slab, en);
 228 }
 229
 230 /*
 231  * Flow to release an extent_node:
 232  * 1. list_del_init
 233  * 2. __detach_extent_node
 234  * 3. kmem_cache_free.
 235  */
 236 static void __release_extent_node(struct f2fs_sb_info *sbi,
 237                         struct extent_tree *et, struct extent_node *en)
 238 {
 239         spin_lock(&sbi->extent_lock);
 240         f2fs_bug_on(sbi, list_empty(&en->list));
 241         list_del_init(&en->list);
 242         spin_unlock(&sbi->extent_lock);
 243
 244         __detach_extent_node(sbi, et, en);
 245 }
 246
 247 static struct extent_tree *__grab_extent_tree(struct inode *inode)
 248 {
 249         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 250         struct extent_tree *et;
 251         nid_t ino = inode->i_ino;
 252
 253         mutex_lock(&sbi->extent_tree_lock);
 254         et = radix_tree_lookup(&sbi->extent_tree_root, ino);
 255         if (!et) {
 256                 et = f2fs_kmem_cache_alloc(extent_tree_slab, GFP_NOFS);
 257                 f2fs_radix_tree_insert(&sbi->extent_tree_root, ino, et);
 258                 memset(et, 0, sizeof(struct extent_tree));
 259                 et->ino = ino;
 260                 et->root = RB_ROOT;
 261                 et->cached_en = NULL;
 262                 rwlock_init(&et->lock);
 263                 INIT_LIST_HEAD(&et->list);
 264                 atomic_set(&et->node_cnt, 0);
 265                 atomic_inc(&sbi->total_ext_tree);
 266         } else {
 267                 atomic_dec(&sbi->total_zombie_tree);
 268                 list_del_init(&et->list);
 269         }
 270         mutex_unlock(&sbi->extent_tree_lock);
 271
 272         /* never died until evict_inode */
 273         F2FS_I(inode)->extent_tree = et;
 274
 275         return et;
 276 }
 277
 278 static struct extent_node *__init_extent_tree(struct f2fs_sb_info *sbi,
 279                                 struct extent_tree *et, struct extent_info *ei)
 280 {
 281         struct rb_node **p = &et->root.rb_node;
 282         struct extent_node *en;
 283
 284         en = __attach_extent_node(sbi, et, ei, NULL, p);
 285         if (!en)
 286                 return NULL;
 287
 288         et->largest = en->ei;
 289         et->cached_en = en;
 290         return en;
 291 }
 292
 293 static unsigned int __free_extent_tree(struct f2fs_sb_info *sbi,
 294                                         struct extent_tree *et)
 295 {
 296         struct rb_node *node, *next;
 297         struct extent_node *en;
 298         unsigned int count = atomic_read(&et->node_cnt);
 299
 300         node = rb_first(&et->root);
 301         while (node) {
 302                 next = rb_next(node);
 303                 en = rb_entry(node, struct extent_node, rb_node);
 304                 __release_extent_node(sbi, et, en);
 305                 node = next;
 306         }
 307
 308         return count - atomic_read(&et->node_cnt);
 309 }
 310
 311 static void __drop_largest_extent(struct inode *inode,
 312                                         pgoff_t fofs, unsigned int len)
 313 {
 314         struct extent_info *largest = &F2FS_I(inode)->extent_tree->largest;
 315
 316         if (fofs < largest->fofs + largest->len && fofs + len > largest->fofs) {
 317                 largest->len = 0;
 318                 f2fs_mark_inode_dirty_sync(inode, true);
 319         }
 320 }
 321
 322 /* return true, if inode page is changed */
 323 static bool __f2fs_init_extent_tree(struct inode *inode, struct f2fs_extent *i_ext)
 324 {
 325         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 326         struct extent_tree *et;
 327         struct extent_node *en;
 328         struct extent_info ei;
 329
 330         if (!f2fs_may_extent_tree(inode)) {
 331                 /* drop largest extent */
 332                 if (i_ext && i_ext->len) {
 333                         i_ext->len = 0;
 334                         return true;
 335                 }
 336                 return false;
 337         }
 338
 339         et = __grab_extent_tree(inode);
 340
 341         if (!i_ext || !i_ext->len)
 342                 return false;
 343
 344         get_extent_info(&ei, i_ext);
 345
 346         write_lock(&et->lock);
 347         if (atomic_read(&et->node_cnt))
 348                 goto out;
 349
 350         en = __init_extent_tree(sbi, et, &ei);
 351         if (en) {
 352                 spin_lock(&sbi->extent_lock);
 353                 list_add_tail(&en->list, &sbi->extent_list);
 354                 spin_unlock(&sbi->extent_lock);
 355         }
 356 out:
 357         write_unlock(&et->lock);
 358         return false;
 359 }
 360
 361 bool f2fs_init_extent_tree(struct inode *inode, struct f2fs_extent *i_ext)
 362 {
 363         bool ret =  __f2fs_init_extent_tree(inode, i_ext);
 364
 365         if (!F2FS_I(inode)->extent_tree)
 366                 set_inode_flag(inode, FI_NO_EXTENT);
 367
 368         return ret;
 369 }
 370
 371 static bool f2fs_lookup_extent_tree(struct inode *inode, pgoff_t pgofs,
 372                                                         struct extent_info *ei)
 373 {
 374         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 375         struct extent_tree *et = F2FS_I(inode)->extent_tree;
 376         struct extent_node *en;
 377         bool ret = false;
 378
 379         f2fs_bug_on(sbi, !et);
 380
 381         trace_f2fs_lookup_extent_tree_start(inode, pgofs);
 382
 383         read_lock(&et->lock);
 384
 385         if (et->largest.fofs <= pgofs &&
 386                         et->largest.fofs + et->largest.len > pgofs) {
 387                 *ei = et->largest;
 388                 ret = true;
 389                 stat_inc_largest_node_hit(sbi);
 390                 goto out;
 391         }
 392
 393         en = (struct extent_node *)__lookup_rb_tree(&et->root,
 394                                 (struct rb_entry *)et->cached_en, pgofs);
 395         if (!en)
 396                 goto out;
 397
 398         if (en == et->cached_en)
 399                 stat_inc_cached_node_hit(sbi);
 400         else
 401                 stat_inc_rbtree_node_hit(sbi);
 402
 403         *ei = en->ei;
 404         spin_lock(&sbi->extent_lock);
 405         if (!list_empty(&en->list)) {
 406                 list_move_tail(&en->list, &sbi->extent_list);
 407                 et->cached_en = en;
 408         }
 409         spin_unlock(&sbi->extent_lock);
 410         ret = true;
 411 out:
 412         stat_inc_total_hit(sbi);
 413         read_unlock(&et->lock);
 414
 415         trace_f2fs_lookup_extent_tree_end(inode, pgofs, ei);
 416         return ret;
 417 }
 418
 419 static struct extent_node *__try_merge_extent_node(struct inode *inode,
 420                                 struct extent_tree *et, struct extent_info *ei,
 421                                 struct extent_node *prev_ex,
 422                                 struct extent_node *next_ex)
 423 {
 424         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 425         struct extent_node *en = NULL;
 426
 427         if (prev_ex && __is_back_mergeable(ei, &prev_ex->ei)) {
 428                 prev_ex->ei.len += ei->len;
 429                 ei = &prev_ex->ei;
 430                 en = prev_ex;
 431         }
 432
 433         if (next_ex && __is_front_mergeable(ei, &next_ex->ei)) {
 434                 next_ex->ei.fofs = ei->fofs;
 435                 next_ex->ei.blk = ei->blk;
 436                 next_ex->ei.len += ei->len;
 437                 if (en)
 438                         __release_extent_node(sbi, et, prev_ex);
 439
 440                 en = next_ex;
 441         }
 442
 443         if (!en)
 444                 return NULL;
 445
 446         __try_update_largest_extent(inode, et, en);
 447
 448         spin_lock(&sbi->extent_lock);
 449         if (!list_empty(&en->list)) {
 450                 list_move_tail(&en->list, &sbi->extent_list);
 451                 et->cached_en = en;
 452         }
 453         spin_unlock(&sbi->extent_lock);
 454         return en;
 455 }
 456
 457 static struct extent_node *__insert_extent_tree(struct inode *inode,
 458                                 struct extent_tree *et, struct extent_info *ei,
 459                                 struct rb_node **insert_p,
 460                                 struct rb_node *insert_parent)
 461 {
 462         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 463         struct rb_node **p = &et->root.rb_node;
 464         struct rb_node *parent = NULL;
 465         struct extent_node *en = NULL;
 466
 467         if (insert_p && insert_parent) {
 468                 parent = insert_parent;
 469                 p = insert_p;
 470                 goto do_insert;
 471         }
 472
 473         p = __lookup_rb_tree_for_insert(sbi, &et->root, &parent, ei->fofs);
 474 do_insert:
 475         en = __attach_extent_node(sbi, et, ei, parent, p);
 476         if (!en)
 477                 return NULL;
 478
 479         __try_update_largest_extent(inode, et, en);
 480
 481         /* update in global extent list */
 482         spin_lock(&sbi->extent_lock);
 483         list_add_tail(&en->list, &sbi->extent_list);
 484         et->cached_en = en;
 485         spin_unlock(&sbi->extent_lock);
 486         return en;
 487 }
 488
 489 static void f2fs_update_extent_tree_range(struct inode *inode,
 490                                 pgoff_t fofs, block_t blkaddr, unsigned int len)
 491 {
 492         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 493         struct extent_tree *et = F2FS_I(inode)->extent_tree;
 494         struct extent_node *en = NULL, *en1 = NULL;
 495         struct extent_node *prev_en = NULL, *next_en = NULL;
 496         struct extent_info ei, dei, prev;
 497         struct rb_node **insert_p = NULL, *insert_parent = NULL;
 498         unsigned int end = fofs + len;
 499         unsigned int pos = (unsigned int)fofs;
 500
 501         if (!et)
 502                 return;
 503
 504         trace_f2fs_update_extent_tree_range(inode, fofs, blkaddr, len);
 505
 506         write_lock(&et->lock);
 507
 508         if (is_inode_flag_set(inode, FI_NO_EXTENT)) {
 509                 write_unlock(&et->lock);
 510                 return;
 511         }
 512
 513         prev = et->largest;
 514         dei.len = 0;
 515
 516         /*
 517          * drop largest extent before lookup, in case it's already
 518          * been shrunk from extent tree
 519          */
 520         __drop_largest_extent(inode, fofs, len);
 521
 522         /* 1. lookup first extent node in range [fofs, fofs + len - 1] */
 523         en = (struct extent_node *)__lookup_rb_tree_ret(&et->root,
 524                                         (struct rb_entry *)et->cached_en, fofs,
 525                                         (struct rb_entry **)&prev_en,
 526                                         (struct rb_entry **)&next_en,
 527                                         &insert_p, &insert_parent, false);
 528         if (!en)
 529                 en = next_en;
 530
 531         /* 2. invlidate all extent nodes in range [fofs, fofs + len - 1] */
 532         while (en && en->ei.fofs < end) {
 533                 unsigned int org_end;
 534                 int parts = 0;  /* # of parts current extent split into */
 535
 536                 next_en = en1 = NULL;
 537
 538                 dei = en->ei;
 539                 org_end = dei.fofs + dei.len;
 540                 f2fs_bug_on(sbi, pos >= org_end);
 541
 542                 if (pos > dei.fofs &&   pos - dei.fofs >= F2FS_MIN_EXTENT_LEN) {
 543                         en->ei.len = pos - en->ei.fofs;
 544                         prev_en = en;
 545                         parts = 1;
 546                 }
 547
 548                 if (end < org_end && org_end - end >= F2FS_MIN_EXTENT_LEN) {
 549                         if (parts) {
 550                                 set_extent_info(&ei, end,
 551                                                 end - dei.fofs + dei.blk,
 552                                                 org_end - end);
 553                                 en1 = __insert_extent_tree(inode, et, &ei,
 554                                                         NULL, NULL);
 555                                 next_en = en1;
 556                         } else {
 557                                 en->ei.fofs = end;
 558                                 en->ei.blk += end - dei.fofs;
 559                                 en->ei.len -= end - dei.fofs;
 560                                 next_en = en;
 561                         }
 562                         parts++;
 563                 }
 564
 565                 if (!next_en) {
 566                         struct rb_node *node = rb_next(&en->rb_node);
 567
 568                         next_en = rb_entry_safe(node, struct extent_node,
 569                                                 rb_node);
 570                 }
 571
 572                 if (parts)
 573                         __try_update_largest_extent(inode, et, en);
 574                 else
 575                         __release_extent_node(sbi, et, en);
 576
 577                 /*
 578                  * if original extent is split into zero or two parts, extent
 579                  * tree has been altered by deletion or insertion, therefore
 580                  * invalidate pointers regard to tree.
 581                  */
 582                 if (parts != 1) {
 583                         insert_p = NULL;
 584                         insert_parent = NULL;
 585                 }
 586                 en = next_en;
 587         }
 588
 589         /* 3. update extent in extent cache */
 590         if (blkaddr) {
 591
 592                 set_extent_info(&ei, fofs, blkaddr, len);
 593                 if (!__try_merge_extent_node(inode, et, &ei, prev_en, next_en))
 594                         __insert_extent_tree(inode, et, &ei,
 595                                                 insert_p, insert_parent);
 596
 597                 /* give up extent_cache, if split and small updates happen */
 598                 if (dei.len >= 1 &&
 599                                 prev.len < F2FS_MIN_EXTENT_LEN &&
 600                                 et->largest.len < F2FS_MIN_EXTENT_LEN) {
 601                         __drop_largest_extent(inode, 0, UINT_MAX);
 602                         set_inode_flag(inode, FI_NO_EXTENT);
 603                 }
 604         }
 605
 606         if (is_inode_flag_set(inode, FI_NO_EXTENT))
 607                 __free_extent_tree(sbi, et);
 608
 609         write_unlock(&et->lock);
 610 }
 611
 612 unsigned int f2fs_shrink_extent_tree(struct f2fs_sb_info *sbi, int nr_shrink)
 613 {
 614         struct extent_tree *et, *next;
 615         struct extent_node *en;
 616         unsigned int node_cnt = 0, tree_cnt = 0;
 617         int remained;
 618
 619         if (!test_opt(sbi, EXTENT_CACHE))
 620                 return 0;
 621
 622         if (!atomic_read(&sbi->total_zombie_tree))
 623                 goto free_node;
 624
 625         if (!mutex_trylock(&sbi->extent_tree_lock))
 626                 goto out;
 627
 628         /* 1. remove unreferenced extent tree */
 629         list_for_each_entry_safe(et, next, &sbi->zombie_list, list) {
 630                 if (atomic_read(&et->node_cnt)) {
 631                         write_lock(&et->lock);
 632                         node_cnt += __free_extent_tree(sbi, et);
 633                         write_unlock(&et->lock);
 634                 }
 635                 f2fs_bug_on(sbi, atomic_read(&et->node_cnt));
 636                 list_del_init(&et->list);
 637                 radix_tree_delete(&sbi->extent_tree_root, et->ino);
 638                 kmem_cache_free(extent_tree_slab, et);
 639                 atomic_dec(&sbi->total_ext_tree);
 640                 atomic_dec(&sbi->total_zombie_tree);
 641                 tree_cnt++;
 642
 643                 if (node_cnt + tree_cnt >= nr_shrink)
 644                         goto unlock_out;
 645                 cond_resched();
 646         }
 647         mutex_unlock(&sbi->extent_tree_lock);
 648
 649 free_node:
 650         /* 2. remove LRU extent entries */
 651         if (!mutex_trylock(&sbi->extent_tree_lock))
 652                 goto out;
 653
 654         remained = nr_shrink - (node_cnt + tree_cnt);
 655
 656         spin_lock(&sbi->extent_lock);
 657         for (; remained > 0; remained--) {
 658                 if (list_empty(&sbi->extent_list))
 659                         break;
 660                 en = list_first_entry(&sbi->extent_list,
 661                                         struct extent_node, list);
 662                 et = en->et;
 663                 if (!write_trylock(&et->lock)) {
 664                         /* refresh this extent node's position in extent list */
 665                         list_move_tail(&en->list, &sbi->extent_list);
 666                         continue;
 667                 }
 668
 669                 list_del_init(&en->list);
 670                 spin_unlock(&sbi->extent_lock);
 671
 672                 __detach_extent_node(sbi, et, en);
 673
 674                 write_unlock(&et->lock);
 675                 node_cnt++;
 676                 spin_lock(&sbi->extent_lock);
 677         }
 678         spin_unlock(&sbi->extent_lock);
 679
 680 unlock_out:
 681         mutex_unlock(&sbi->extent_tree_lock);
 682 out:
 683         trace_f2fs_shrink_extent_tree(sbi, node_cnt, tree_cnt);
 684
 685         return node_cnt + tree_cnt;
 686 }
 687
 688 unsigned int f2fs_destroy_extent_node(struct inode *inode)
 689 {
 690         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 691         struct extent_tree *et = F2FS_I(inode)->extent_tree;
 692         unsigned int node_cnt = 0;
 693
 694         if (!et || !atomic_read(&et->node_cnt))
 695                 return 0;
 696
 697         write_lock(&et->lock);
 698         node_cnt = __free_extent_tree(sbi, et);
 699         write_unlock(&et->lock);
 700
 701         return node_cnt;
 702 }
 703
 704 void f2fs_drop_extent_tree(struct inode *inode)
 705 {
 706         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 707         struct extent_tree *et = F2FS_I(inode)->extent_tree;
 708
 709         set_inode_flag(inode, FI_NO_EXTENT);
 710
 711         write_lock(&et->lock);
 712         __free_extent_tree(sbi, et);
 713         __drop_largest_extent(inode, 0, UINT_MAX);
 714         write_unlock(&et->lock);
 715 }
 716
 717 void f2fs_destroy_extent_tree(struct inode *inode)
 718 {
 719         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 720         struct extent_tree *et = F2FS_I(inode)->extent_tree;
 721         unsigned int node_cnt = 0;
 722
 723         if (!et)
 724                 return;
 725
 726         if (inode->i_nlink && !is_bad_inode(inode) &&
 727                                         atomic_read(&et->node_cnt)) {
 728                 mutex_lock(&sbi->extent_tree_lock);
 729                 list_add_tail(&et->list, &sbi->zombie_list);
 730                 atomic_inc(&sbi->total_zombie_tree);
 731                 mutex_unlock(&sbi->extent_tree_lock);
 732                 return;
 733         }
 734
 735         /* free all extent info belong to this extent tree */
 736         node_cnt = f2fs_destroy_extent_node(inode);
 737
 738         /* delete extent tree entry in radix tree */
 739         mutex_lock(&sbi->extent_tree_lock);
 740         f2fs_bug_on(sbi, atomic_read(&et->node_cnt));
 741         radix_tree_delete(&sbi->extent_tree_root, inode->i_ino);
 742         kmem_cache_free(extent_tree_slab, et);
 743         atomic_dec(&sbi->total_ext_tree);
 744         mutex_unlock(&sbi->extent_tree_lock);
 745
 746         F2FS_I(inode)->extent_tree = NULL;
 747
 748         trace_f2fs_destroy_extent_tree(inode, node_cnt);
 749 }
 750
 751 bool f2fs_lookup_extent_cache(struct inode *inode, pgoff_t pgofs,
 752                                         struct extent_info *ei)
 753 {
 754         if (!f2fs_may_extent_tree(inode))
 755                 return false;
 756
 757         return f2fs_lookup_extent_tree(inode, pgofs, ei);
 758 }
 759
 760 void f2fs_update_extent_cache(struct dnode_of_data *dn)
 761 {
 762         pgoff_t fofs;
 763         block_t blkaddr;
 764
 765         if (!f2fs_may_extent_tree(dn->inode))
 766                 return;
 767
 768         if (dn->data_blkaddr == NEW_ADDR)
 769                 blkaddr = NULL_ADDR;
 770         else
 771                 blkaddr = dn->data_blkaddr;
 772
 773         fofs = start_bidx_of_node(ofs_of_node(dn->node_page), dn->inode) +
 774                                                                 dn->ofs_in_node;
 775         f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, 1);
 776 }
 777
 778 void f2fs_update_extent_cache_range(struct dnode_of_data *dn,
 779                                 pgoff_t fofs, block_t blkaddr, unsigned int len)
 780
 781 {
 782         if (!f2fs_may_extent_tree(dn->inode))
 783                 return;
 784
 785         f2fs_update_extent_tree_range(dn->inode, fofs, blkaddr, len);
 786 }
 787
 788 void init_extent_cache_info(struct f2fs_sb_info *sbi)
 789 {
 790         INIT_RADIX_TREE(&sbi->extent_tree_root, GFP_NOIO);
 791         mutex_init(&sbi->extent_tree_lock);
 792         INIT_LIST_HEAD(&sbi->extent_list);
 793         spin_lock_init(&sbi->extent_lock);
 794         atomic_set(&sbi->total_ext_tree, 0);
 795         INIT_LIST_HEAD(&sbi->zombie_list);
 796         atomic_set(&sbi->total_zombie_tree, 0);
 797         atomic_set(&sbi->total_ext_node, 0);
 798 }
 799
 800 int __init create_extent_cache(void)
 801 {
 802         extent_tree_slab = f2fs_kmem_cache_create("f2fs_extent_tree",
 803                         sizeof(struct extent_tree));
 804         if (!extent_tree_slab)
 805                 return -ENOMEM;
 806         extent_node_slab = f2fs_kmem_cache_create("f2fs_extent_node",
 807                         sizeof(struct extent_node));
 808         if (!extent_node_slab) {
 809                 kmem_cache_destroy(extent_tree_slab);
 810                 return -ENOMEM;
 811         }
 812         return 0;
 813 }
 814
 815 void destroy_extent_cache(void)
 816 {
 817         kmem_cache_destroy(extent_node_slab);
 818         kmem_cache_destroy(extent_tree_slab);
 819 }