fs/f2fs/node.c

   1 /*
   2  * fs/f2fs/node.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/mpage.h>
  14 #include <linux/backing-dev.h>
  15 #include <linux/blkdev.h>
  16 #include <linux/pagevec.h>
  17 #include <linux/swap.h>
  18
  19 #include "f2fs.h"
  20 #include "node.h"
  21 #include "segment.h"
  22 #include <trace/events/f2fs.h>
  23
  24 #define on_build_free_nids(nmi) mutex_is_locked(&nm_i->build_lock)
  25
  26 static struct kmem_cache *nat_entry_slab;
  27 static struct kmem_cache *free_nid_slab;
  28 static struct kmem_cache *nat_entry_set_slab;
  29
  30 bool available_free_memory(struct f2fs_sb_info *sbi, int type)
  31 {
  32         struct f2fs_nm_info *nm_i = NM_I(sbi);
  33         struct sysinfo val;
  34         unsigned long mem_size = 0;
  35         bool res = false;
  36
  37         si_meminfo(&val);
  38         /* give 25%, 25%, 50% memory for each components respectively */
  39         if (type == FREE_NIDS) {
  40                 mem_size = (nm_i->fcnt * sizeof(struct free_nid)) >> 12;
  41                 res = mem_size < ((val.totalram * nm_i->ram_thresh / 100) >> 2);
  42         } else if (type == NAT_ENTRIES) {
  43                 mem_size = (nm_i->nat_cnt * sizeof(struct nat_entry)) >> 12;
  44                 res = mem_size < ((val.totalram * nm_i->ram_thresh / 100) >> 2);
  45         } else if (type == DIRTY_DENTS) {
  46                 if (sbi->sb->s_bdi->dirty_exceeded)
  47                         return false;
  48                 mem_size = get_pages(sbi, F2FS_DIRTY_DENTS);
  49                 res = mem_size < ((val.totalram * nm_i->ram_thresh / 100) >> 1);
  50         }
  51         return res;
  52 }
  53
  54 static void clear_node_page_dirty(struct page *page)
  55 {
  56         struct address_space *mapping = page->mapping;
  57         struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
  58         unsigned int long flags;
  59
  60         if (PageDirty(page)) {
  61                 spin_lock_irqsave(&mapping->tree_lock, flags);
  62                 radix_tree_tag_clear(&mapping->page_tree,
  63                                 page_index(page),
  64                                 PAGECACHE_TAG_DIRTY);
  65                 spin_unlock_irqrestore(&mapping->tree_lock, flags);
  66
  67                 clear_page_dirty_for_io(page);
  68                 dec_page_count(sbi, F2FS_DIRTY_NODES);
  69         }
  70         ClearPageUptodate(page);
  71 }
  72
  73 static struct page *get_current_nat_page(struct f2fs_sb_info *sbi, nid_t nid)
  74 {
  75         pgoff_t index = current_nat_addr(sbi, nid);
  76         return get_meta_page(sbi, index);
  77 }
  78
  79 static struct page *get_next_nat_page(struct f2fs_sb_info *sbi, nid_t nid)
  80 {
  81         struct page *src_page;
  82         struct page *dst_page;
  83         pgoff_t src_off;
  84         pgoff_t dst_off;
  85         void *src_addr;
  86         void *dst_addr;
  87         struct f2fs_nm_info *nm_i = NM_I(sbi);
  88
  89         src_off = current_nat_addr(sbi, nid);
  90         dst_off = next_nat_addr(sbi, src_off);
  91
  92         /* get current nat block page with lock */
  93         src_page = get_meta_page(sbi, src_off);
  94         dst_page = grab_meta_page(sbi, dst_off);
  95         f2fs_bug_on(PageDirty(src_page));
  96
  97         src_addr = page_address(src_page);
  98         dst_addr = page_address(dst_page);
  99         memcpy(dst_addr, src_addr, PAGE_CACHE_SIZE);
 100         set_page_dirty(dst_page);
 101         f2fs_put_page(src_page, 1);
 102
 103         set_to_next_nat(nm_i, nid);
 104
 105         return dst_page;
 106 }
 107
 108 static struct nat_entry *__lookup_nat_cache(struct f2fs_nm_info *nm_i, nid_t n)
 109 {
 110         return radix_tree_lookup(&nm_i->nat_root, n);
 111 }
 112
 113 static unsigned int __gang_lookup_nat_cache(struct f2fs_nm_info *nm_i,
 114                 nid_t start, unsigned int nr, struct nat_entry **ep)
 115 {
 116         return radix_tree_gang_lookup(&nm_i->nat_root, (void **)ep, start, nr);
 117 }
 118
 119 static void __del_from_nat_cache(struct f2fs_nm_info *nm_i, struct nat_entry *e)
 120 {
 121         list_del(&e->list);
 122         radix_tree_delete(&nm_i->nat_root, nat_get_nid(e));
 123         nm_i->nat_cnt--;
 124         kmem_cache_free(nat_entry_slab, e);
 125 }
 126
 127 int is_checkpointed_node(struct f2fs_sb_info *sbi, nid_t nid)
 128 {
 129         struct f2fs_nm_info *nm_i = NM_I(sbi);
 130         struct nat_entry *e;
 131         int is_cp = 1;
 132
 133         read_lock(&nm_i->nat_tree_lock);
 134         e = __lookup_nat_cache(nm_i, nid);
 135         if (e && !e->checkpointed)
 136                 is_cp = 0;
 137         read_unlock(&nm_i->nat_tree_lock);
 138         return is_cp;
 139 }
 140
 141 bool fsync_mark_done(struct f2fs_sb_info *sbi, nid_t nid)
 142 {
 143         struct f2fs_nm_info *nm_i = NM_I(sbi);
 144         struct nat_entry *e;
 145         bool fsync_done = false;
 146
 147         read_lock(&nm_i->nat_tree_lock);
 148         e = __lookup_nat_cache(nm_i, nid);
 149         if (e)
 150                 fsync_done = e->fsync_done;
 151         read_unlock(&nm_i->nat_tree_lock);
 152         return fsync_done;
 153 }
 154
 155 void fsync_mark_clear(struct f2fs_sb_info *sbi, nid_t nid)
 156 {
 157         struct f2fs_nm_info *nm_i = NM_I(sbi);
 158         struct nat_entry *e;
 159
 160         write_lock(&nm_i->nat_tree_lock);
 161         e = __lookup_nat_cache(nm_i, nid);
 162         if (e)
 163                 e->fsync_done = false;
 164         write_unlock(&nm_i->nat_tree_lock);
 165 }
 166
 167 static struct nat_entry *grab_nat_entry(struct f2fs_nm_info *nm_i, nid_t nid)
 168 {
 169         struct nat_entry *new;
 170
 171         new = kmem_cache_alloc(nat_entry_slab, GFP_ATOMIC);
 172         if (!new)
 173                 return NULL;
 174         if (radix_tree_insert(&nm_i->nat_root, nid, new)) {
 175                 kmem_cache_free(nat_entry_slab, new);
 176                 return NULL;
 177         }
 178         memset(new, 0, sizeof(struct nat_entry));
 179         nat_set_nid(new, nid);
 180         new->checkpointed = true;
 181         list_add_tail(&new->list, &nm_i->nat_entries);
 182         nm_i->nat_cnt++;
 183         return new;
 184 }
 185
 186 static void cache_nat_entry(struct f2fs_nm_info *nm_i, nid_t nid,
 187                                                 struct f2fs_nat_entry *ne)
 188 {
 189         struct nat_entry *e;
 190 retry:
 191         write_lock(&nm_i->nat_tree_lock);
 192         e = __lookup_nat_cache(nm_i, nid);
 193         if (!e) {
 194                 e = grab_nat_entry(nm_i, nid);
 195                 if (!e) {
 196                         write_unlock(&nm_i->nat_tree_lock);
 197                         goto retry;
 198                 }
 199                 node_info_from_raw_nat(&e->ni, ne);
 200         }
 201         write_unlock(&nm_i->nat_tree_lock);
 202 }
 203
 204 static void set_node_addr(struct f2fs_sb_info *sbi, struct node_info *ni,
 205                         block_t new_blkaddr, bool fsync_done)
 206 {
 207         struct f2fs_nm_info *nm_i = NM_I(sbi);
 208         struct nat_entry *e;
 209 retry:
 210         write_lock(&nm_i->nat_tree_lock);
 211         e = __lookup_nat_cache(nm_i, ni->nid);
 212         if (!e) {
 213                 e = grab_nat_entry(nm_i, ni->nid);
 214                 if (!e) {
 215                         write_unlock(&nm_i->nat_tree_lock);
 216                         goto retry;
 217                 }
 218                 e->ni = *ni;
 219                 f2fs_bug_on(ni->blk_addr == NEW_ADDR);
 220         } else if (new_blkaddr == NEW_ADDR) {
 221                 /*
 222                  * when nid is reallocated,
 223                  * previous nat entry can be remained in nat cache.
 224                  * So, reinitialize it with new information.
 225                  */
 226                 e->ni = *ni;
 227                 f2fs_bug_on(ni->blk_addr != NULL_ADDR);
 228         }
 229
 230         /* sanity check */
 231         f2fs_bug_on(nat_get_blkaddr(e) != ni->blk_addr);
 232         f2fs_bug_on(nat_get_blkaddr(e) == NULL_ADDR &&
 233                         new_blkaddr == NULL_ADDR);
 234         f2fs_bug_on(nat_get_blkaddr(e) == NEW_ADDR &&
 235                         new_blkaddr == NEW_ADDR);
 236         f2fs_bug_on(nat_get_blkaddr(e) != NEW_ADDR &&
 237                         nat_get_blkaddr(e) != NULL_ADDR &&
 238                         new_blkaddr == NEW_ADDR);
 239
 240         /* increment version no as node is removed */
 241         if (nat_get_blkaddr(e) != NEW_ADDR && new_blkaddr == NULL_ADDR) {
 242                 unsigned char version = nat_get_version(e);
 243                 nat_set_version(e, inc_node_version(version));
 244         }
 245
 246         /* change address */
 247         nat_set_blkaddr(e, new_blkaddr);
 248         __set_nat_cache_dirty(nm_i, e);
 249
 250         /* update fsync_mark if its inode nat entry is still alive */
 251         e = __lookup_nat_cache(nm_i, ni->ino);
 252         if (e)
 253                 e->fsync_done = fsync_done;
 254         write_unlock(&nm_i->nat_tree_lock);
 255 }
 256
 257 int try_to_free_nats(struct f2fs_sb_info *sbi, int nr_shrink)
 258 {
 259         struct f2fs_nm_info *nm_i = NM_I(sbi);
 260
 261         if (available_free_memory(sbi, NAT_ENTRIES))
 262                 return 0;
 263
 264         write_lock(&nm_i->nat_tree_lock);
 265         while (nr_shrink && !list_empty(&nm_i->nat_entries)) {
 266                 struct nat_entry *ne;
 267                 ne = list_first_entry(&nm_i->nat_entries,
 268                                         struct nat_entry, list);
 269                 __del_from_nat_cache(nm_i, ne);
 270                 nr_shrink--;
 271         }
 272         write_unlock(&nm_i->nat_tree_lock);
 273         return nr_shrink;
 274 }
 275
 276 /*
 277  * This function always returns success
 278  */
 279 void get_node_info(struct f2fs_sb_info *sbi, nid_t nid, struct node_info *ni)
 280 {
 281         struct f2fs_nm_info *nm_i = NM_I(sbi);
 282         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_HOT_DATA);
 283         struct f2fs_summary_block *sum = curseg->sum_blk;
 284         nid_t start_nid = START_NID(nid);
 285         struct f2fs_nat_block *nat_blk;
 286         struct page *page = NULL;
 287         struct f2fs_nat_entry ne;
 288         struct nat_entry *e;
 289         int i;
 290
 291         memset(&ne, 0, sizeof(struct f2fs_nat_entry));
 292         ni->nid = nid;
 293
 294         /* Check nat cache */
 295         read_lock(&nm_i->nat_tree_lock);
 296         e = __lookup_nat_cache(nm_i, nid);
 297         if (e) {
 298                 ni->ino = nat_get_ino(e);
 299                 ni->blk_addr = nat_get_blkaddr(e);
 300                 ni->version = nat_get_version(e);
 301         }
 302         read_unlock(&nm_i->nat_tree_lock);
 303         if (e)
 304                 return;
 305
 306         /* Check current segment summary */
 307         mutex_lock(&curseg->curseg_mutex);
 308         i = lookup_journal_in_cursum(sum, NAT_JOURNAL, nid, 0);
 309         if (i >= 0) {
 310                 ne = nat_in_journal(sum, i);
 311                 node_info_from_raw_nat(ni, &ne);
 312         }
 313         mutex_unlock(&curseg->curseg_mutex);
 314         if (i >= 0)
 315                 goto cache;
 316
 317         /* Fill node_info from nat page */
 318         page = get_current_nat_page(sbi, start_nid);
 319         nat_blk = (struct f2fs_nat_block *)page_address(page);
 320         ne = nat_blk->entries[nid - start_nid];
 321         node_info_from_raw_nat(ni, &ne);
 322         f2fs_put_page(page, 1);
 323 cache:
 324         /* cache nat entry */
 325         cache_nat_entry(NM_I(sbi), nid, &ne);
 326 }
 327
 328 /*
 329  * The maximum depth is four.
 330  * Offset[0] will have raw inode offset.
 331  */
 332 static int get_node_path(struct f2fs_inode_info *fi, long block,
 333                                 int offset[4], unsigned int noffset[4])
 334 {
 335         const long direct_index = ADDRS_PER_INODE(fi);
 336         const long direct_blks = ADDRS_PER_BLOCK;
 337         const long dptrs_per_blk = NIDS_PER_BLOCK;
 338         const long indirect_blks = ADDRS_PER_BLOCK * NIDS_PER_BLOCK;
 339         const long dindirect_blks = indirect_blks * NIDS_PER_BLOCK;
 340         int n = 0;
 341         int level = 0;
 342
 343         noffset[0] = 0;
 344
 345         if (block < direct_index) {
 346                 offset[n] = block;
 347                 goto got;
 348         }
 349         block -= direct_index;
 350         if (block < direct_blks) {
 351                 offset[n++] = NODE_DIR1_BLOCK;
 352                 noffset[n] = 1;
 353                 offset[n] = block;
 354                 level = 1;
 355                 goto got;
 356         }
 357         block -= direct_blks;
 358         if (block < direct_blks) {
 359                 offset[n++] = NODE_DIR2_BLOCK;
 360                 noffset[n] = 2;
 361                 offset[n] = block;
 362                 level = 1;
 363                 goto got;
 364         }
 365         block -= direct_blks;
 366         if (block < indirect_blks) {
 367                 offset[n++] = NODE_IND1_BLOCK;
 368                 noffset[n] = 3;
 369                 offset[n++] = block / direct_blks;
 370                 noffset[n] = 4 + offset[n - 1];
 371                 offset[n] = block % direct_blks;
 372                 level = 2;
 373                 goto got;
 374         }
 375         block -= indirect_blks;
 376         if (block < indirect_blks) {
 377                 offset[n++] = NODE_IND2_BLOCK;
 378                 noffset[n] = 4 + dptrs_per_blk;
 379                 offset[n++] = block / direct_blks;
 380                 noffset[n] = 5 + dptrs_per_blk + offset[n - 1];
 381                 offset[n] = block % direct_blks;
 382                 level = 2;
 383                 goto got;
 384         }
 385         block -= indirect_blks;
 386         if (block < dindirect_blks) {
 387                 offset[n++] = NODE_DIND_BLOCK;
 388                 noffset[n] = 5 + (dptrs_per_blk * 2);
 389                 offset[n++] = block / indirect_blks;
 390                 noffset[n] = 6 + (dptrs_per_blk * 2) +
 391                               offset[n - 1] * (dptrs_per_blk + 1);
 392                 offset[n++] = (block / direct_blks) % dptrs_per_blk;
 393                 noffset[n] = 7 + (dptrs_per_blk * 2) +
 394                               offset[n - 2] * (dptrs_per_blk + 1) +
 395                               offset[n - 1];
 396                 offset[n] = block % direct_blks;
 397                 level = 3;
 398                 goto got;
 399         } else {
 400                 BUG();
 401         }
 402 got:
 403         return level;
 404 }
 405
 406 /*
 407  * Caller should call f2fs_put_dnode(dn).
 408  * Also, it should grab and release a rwsem by calling f2fs_lock_op() and
 409  * f2fs_unlock_op() only if ro is not set RDONLY_NODE.
 410  * In the case of RDONLY_NODE, we don't need to care about mutex.
 411  */
 412 int get_dnode_of_data(struct dnode_of_data *dn, pgoff_t index, int mode)
 413 {
 414         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
 415         struct page *npage[4];
 416         struct page *parent;
 417         int offset[4];
 418         unsigned int noffset[4];
 419         nid_t nids[4];
 420         int level, i;
 421         int err = 0;
 422
 423         level = get_node_path(F2FS_I(dn->inode), index, offset, noffset);
 424
 425         nids[0] = dn->inode->i_ino;
 426         npage[0] = dn->inode_page;
 427
 428         if (!npage[0]) {
 429                 npage[0] = get_node_page(sbi, nids[0]);
 430                 if (IS_ERR(npage[0]))
 431                         return PTR_ERR(npage[0]);
 432         }
 433         parent = npage[0];
 434         if (level != 0)
 435                 nids[1] = get_nid(parent, offset[0], true);
 436         dn->inode_page = npage[0];
 437         dn->inode_page_locked = true;
 438
 439         /* get indirect or direct nodes */
 440         for (i = 1; i <= level; i++) {
 441                 bool done = false;
 442
 443                 if (!nids[i] && mode == ALLOC_NODE) {
 444                         /* alloc new node */
 445                         if (!alloc_nid(sbi, &(nids[i]))) {
 446                                 err = -ENOSPC;
 447                                 goto release_pages;
 448                         }
 449
 450                         dn->nid = nids[i];
 451                         npage[i] = new_node_page(dn, noffset[i], NULL);
 452                         if (IS_ERR(npage[i])) {
 453                                 alloc_nid_failed(sbi, nids[i]);
 454                                 err = PTR_ERR(npage[i]);
 455                                 goto release_pages;
 456                         }
 457
 458                         set_nid(parent, offset[i - 1], nids[i], i == 1);
 459                         alloc_nid_done(sbi, nids[i]);
 460                         done = true;
 461                 } else if (mode == LOOKUP_NODE_RA && i == level && level > 1) {
 462                         npage[i] = get_node_page_ra(parent, offset[i - 1]);
 463                         if (IS_ERR(npage[i])) {
 464                                 err = PTR_ERR(npage[i]);
 465                                 goto release_pages;
 466                         }
 467                         done = true;
 468                 }
 469                 if (i == 1) {
 470                         dn->inode_page_locked = false;
 471                         unlock_page(parent);
 472                 } else {
 473                         f2fs_put_page(parent, 1);
 474                 }
 475
 476                 if (!done) {
 477                         npage[i] = get_node_page(sbi, nids[i]);
 478                         if (IS_ERR(npage[i])) {
 479                                 err = PTR_ERR(npage[i]);
 480                                 f2fs_put_page(npage[0], 0);
 481                                 goto release_out;
 482                         }
 483                 }
 484                 if (i < level) {
 485                         parent = npage[i];
 486                         nids[i + 1] = get_nid(parent, offset[i], false);
 487                 }
 488         }
 489         dn->nid = nids[level];
 490         dn->ofs_in_node = offset[level];
 491         dn->node_page = npage[level];
 492         dn->data_blkaddr = datablock_addr(dn->node_page, dn->ofs_in_node);
 493         return 0;
 494
 495 release_pages:
 496         f2fs_put_page(parent, 1);
 497         if (i > 1)
 498                 f2fs_put_page(npage[0], 0);
 499 release_out:
 500         dn->inode_page = NULL;
 501         dn->node_page = NULL;
 502         return err;
 503 }
 504
 505 static void truncate_node(struct dnode_of_data *dn)
 506 {
 507         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
 508         struct node_info ni;
 509
 510         get_node_info(sbi, dn->nid, &ni);
 511         if (dn->inode->i_blocks == 0) {
 512                 f2fs_bug_on(ni.blk_addr != NULL_ADDR);
 513                 goto invalidate;
 514         }
 515         f2fs_bug_on(ni.blk_addr == NULL_ADDR);
 516
 517         /* Deallocate node address */
 518         invalidate_blocks(sbi, ni.blk_addr);
 519         dec_valid_node_count(sbi, dn->inode);
 520         set_node_addr(sbi, &ni, NULL_ADDR, false);
 521
 522         if (dn->nid == dn->inode->i_ino) {
 523                 remove_orphan_inode(sbi, dn->nid);
 524                 dec_valid_inode_count(sbi);
 525         } else {
 526                 sync_inode_page(dn);
 527         }
 528 invalidate:
 529         clear_node_page_dirty(dn->node_page);
 530         F2FS_SET_SB_DIRT(sbi);
 531
 532         f2fs_put_page(dn->node_page, 1);
 533
 534         invalidate_mapping_pages(NODE_MAPPING(sbi),
 535                         dn->node_page->index, dn->node_page->index);
 536
 537         dn->node_page = NULL;
 538         trace_f2fs_truncate_node(dn->inode, dn->nid, ni.blk_addr);
 539 }
 540
 541 static int truncate_dnode(struct dnode_of_data *dn)
 542 {
 543         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
 544         struct page *page;
 545
 546         if (dn->nid == 0)
 547                 return 1;
 548
 549         /* get direct node */
 550         page = get_node_page(sbi, dn->nid);
 551         if (IS_ERR(page) && PTR_ERR(page) == -ENOENT)
 552                 return 1;
 553         else if (IS_ERR(page))
 554                 return PTR_ERR(page);
 555
 556         /* Make dnode_of_data for parameter */
 557         dn->node_page = page;
 558         dn->ofs_in_node = 0;
 559         truncate_data_blocks(dn);
 560         truncate_node(dn);
 561         return 1;
 562 }
 563
 564 static int truncate_nodes(struct dnode_of_data *dn, unsigned int nofs,
 565                                                 int ofs, int depth)
 566 {
 567         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
 568         struct dnode_of_data rdn = *dn;
 569         struct page *page;
 570         struct f2fs_node *rn;
 571         nid_t child_nid;
 572         unsigned int child_nofs;
 573         int freed = 0;
 574         int i, ret;
 575
 576         if (dn->nid == 0)
 577                 return NIDS_PER_BLOCK + 1;
 578
 579         trace_f2fs_truncate_nodes_enter(dn->inode, dn->nid, dn->data_blkaddr);
 580
 581         page = get_node_page(sbi, dn->nid);
 582         if (IS_ERR(page)) {
 583                 trace_f2fs_truncate_nodes_exit(dn->inode, PTR_ERR(page));
 584                 return PTR_ERR(page);
 585         }
 586
 587         rn = F2FS_NODE(page);
 588         if (depth < 3) {
 589                 for (i = ofs; i < NIDS_PER_BLOCK; i++, freed++) {
 590                         child_nid = le32_to_cpu(rn->in.nid[i]);
 591                         if (child_nid == 0)
 592                                 continue;
 593                         rdn.nid = child_nid;
 594                         ret = truncate_dnode(&rdn);
 595                         if (ret < 0)
 596                                 goto out_err;
 597                         set_nid(page, i, 0, false);
 598                 }
 599         } else {
 600                 child_nofs = nofs + ofs * (NIDS_PER_BLOCK + 1) + 1;
 601                 for (i = ofs; i < NIDS_PER_BLOCK; i++) {
 602                         child_nid = le32_to_cpu(rn->in.nid[i]);
 603                         if (child_nid == 0) {
 604                                 child_nofs += NIDS_PER_BLOCK + 1;
 605                                 continue;
 606                         }
 607                         rdn.nid = child_nid;
 608                         ret = truncate_nodes(&rdn, child_nofs, 0, depth - 1);
 609                         if (ret == (NIDS_PER_BLOCK + 1)) {
 610                                 set_nid(page, i, 0, false);
 611                                 child_nofs += ret;
 612                         } else if (ret < 0 && ret != -ENOENT) {
 613                                 goto out_err;
 614                         }
 615                 }
 616                 freed = child_nofs;
 617         }
 618
 619         if (!ofs) {
 620                 /* remove current indirect node */
 621                 dn->node_page = page;
 622                 truncate_node(dn);
 623                 freed++;
 624         } else {
 625                 f2fs_put_page(page, 1);
 626         }
 627         trace_f2fs_truncate_nodes_exit(dn->inode, freed);
 628         return freed;
 629
 630 out_err:
 631         f2fs_put_page(page, 1);
 632         trace_f2fs_truncate_nodes_exit(dn->inode, ret);
 633         return ret;
 634 }
 635
 636 static int truncate_partial_nodes(struct dnode_of_data *dn,
 637                         struct f2fs_inode *ri, int *offset, int depth)
 638 {
 639         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
 640         struct page *pages[2];
 641         nid_t nid[3];
 642         nid_t child_nid;
 643         int err = 0;
 644         int i;
 645         int idx = depth - 2;
 646
 647         nid[0] = le32_to_cpu(ri->i_nid[offset[0] - NODE_DIR1_BLOCK]);
 648         if (!nid[0])
 649                 return 0;
 650
 651         /* get indirect nodes in the path */
 652         for (i = 0; i < idx + 1; i++) {
 653                 /* reference count'll be increased */
 654                 pages[i] = get_node_page(sbi, nid[i]);
 655                 if (IS_ERR(pages[i])) {
 656                         err = PTR_ERR(pages[i]);
 657                         idx = i - 1;
 658                         goto fail;
 659                 }
 660                 nid[i + 1] = get_nid(pages[i], offset[i + 1], false);
 661         }
 662
 663         /* free direct nodes linked to a partial indirect node */
 664         for (i = offset[idx + 1]; i < NIDS_PER_BLOCK; i++) {
 665                 child_nid = get_nid(pages[idx], i, false);
 666                 if (!child_nid)
 667                         continue;
 668                 dn->nid = child_nid;
 669                 err = truncate_dnode(dn);
 670                 if (err < 0)
 671                         goto fail;
 672                 set_nid(pages[idx], i, 0, false);
 673         }
 674
 675         if (offset[idx + 1] == 0) {
 676                 dn->node_page = pages[idx];
 677                 dn->nid = nid[idx];
 678                 truncate_node(dn);
 679         } else {
 680                 f2fs_put_page(pages[idx], 1);
 681         }
 682         offset[idx]++;
 683         offset[idx + 1] = 0;
 684         idx--;
 685 fail:
 686         for (i = idx; i >= 0; i--)
 687                 f2fs_put_page(pages[i], 1);
 688
 689         trace_f2fs_truncate_partial_nodes(dn->inode, nid, depth, err);
 690
 691         return err;
 692 }
 693
 694 /*
 695  * All the block addresses of data and nodes should be nullified.
 696  */
 697 int truncate_inode_blocks(struct inode *inode, pgoff_t from)
 698 {
 699         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
 700         int err = 0, cont = 1;
 701         int level, offset[4], noffset[4];
 702         unsigned int nofs = 0;
 703         struct f2fs_inode *ri;
 704         struct dnode_of_data dn;
 705         struct page *page;
 706
 707         trace_f2fs_truncate_inode_blocks_enter(inode, from);
 708
 709         level = get_node_path(F2FS_I(inode), from, offset, noffset);
 710 restart:
 711         page = get_node_page(sbi, inode->i_ino);
 712         if (IS_ERR(page)) {
 713                 trace_f2fs_truncate_inode_blocks_exit(inode, PTR_ERR(page));
 714                 return PTR_ERR(page);
 715         }
 716
 717         set_new_dnode(&dn, inode, page, NULL, 0);
 718         unlock_page(page);
 719
 720         ri = F2FS_INODE(page);
 721         switch (level) {
 722         case 0:
 723         case 1:
 724                 nofs = noffset[1];
 725                 break;
 726         case 2:
 727                 nofs = noffset[1];
 728                 if (!offset[level - 1])
 729                         goto skip_partial;
 730                 err = truncate_partial_nodes(&dn, ri, offset, level);
 731                 if (err < 0 && err != -ENOENT)
 732                         goto fail;
 733                 nofs += 1 + NIDS_PER_BLOCK;
 734                 break;
 735         case 3:
 736                 nofs = 5 + 2 * NIDS_PER_BLOCK;
 737                 if (!offset[level - 1])
 738                         goto skip_partial;
 739                 err = truncate_partial_nodes(&dn, ri, offset, level);
 740                 if (err < 0 && err != -ENOENT)
 741                         goto fail;
 742                 break;
 743         default:
 744                 BUG();
 745         }
 746
 747 skip_partial:
 748         while (cont) {
 749                 dn.nid = le32_to_cpu(ri->i_nid[offset[0] - NODE_DIR1_BLOCK]);
 750                 switch (offset[0]) {
 751                 case NODE_DIR1_BLOCK:
 752                 case NODE_DIR2_BLOCK:
 753                         err = truncate_dnode(&dn);
 754                         break;
 755
 756                 case NODE_IND1_BLOCK:
 757                 case NODE_IND2_BLOCK:
 758                         err = truncate_nodes(&dn, nofs, offset[1], 2);
 759                         break;
 760
 761                 case NODE_DIND_BLOCK:
 762                         err = truncate_nodes(&dn, nofs, offset[1], 3);
 763                         cont = 0;
 764                         break;
 765
 766                 default:
 767                         BUG();
 768                 }
 769                 if (err < 0 && err != -ENOENT)
 770                         goto fail;
 771                 if (offset[1] == 0 &&
 772                                 ri->i_nid[offset[0] - NODE_DIR1_BLOCK]) {
 773                         lock_page(page);
 774                         if (unlikely(page->mapping != NODE_MAPPING(sbi))) {
 775                                 f2fs_put_page(page, 1);
 776                                 goto restart;
 777                         }
 778                         f2fs_wait_on_page_writeback(page, NODE);
 779                         ri->i_nid[offset[0] - NODE_DIR1_BLOCK] = 0;
 780                         set_page_dirty(page);
 781                         unlock_page(page);
 782                 }
 783                 offset[1] = 0;
 784                 offset[0]++;
 785                 nofs += err;
 786         }
 787 fail:
 788         f2fs_put_page(page, 0);
 789         trace_f2fs_truncate_inode_blocks_exit(inode, err);
 790         return err > 0 ? 0 : err;
 791 }
 792
 793 int truncate_xattr_node(struct inode *inode, struct page *page)
 794 {
 795         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
 796         nid_t nid = F2FS_I(inode)->i_xattr_nid;
 797         struct dnode_of_data dn;
 798         struct page *npage;
 799
 800         if (!nid)
 801                 return 0;
 802
 803         npage = get_node_page(sbi, nid);
 804         if (IS_ERR(npage))
 805                 return PTR_ERR(npage);
 806
 807         F2FS_I(inode)->i_xattr_nid = 0;
 808
 809         /* need to do checkpoint during fsync */
 810         F2FS_I(inode)->xattr_ver = cur_cp_version(F2FS_CKPT(sbi));
 811
 812         set_new_dnode(&dn, inode, page, npage, nid);
 813
 814         if (page)
 815                 dn.inode_page_locked = true;
 816         truncate_node(&dn);
 817         return 0;
 818 }
 819
 820 /*
 821  * Caller should grab and release a rwsem by calling f2fs_lock_op() and
 822  * f2fs_unlock_op().
 823  */
 824 void remove_inode_page(struct inode *inode)
 825 {
 826         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
 827         struct page *page;
 828         nid_t ino = inode->i_ino;
 829         struct dnode_of_data dn;
 830
 831         page = get_node_page(sbi, ino);
 832         if (IS_ERR(page))
 833                 return;
 834
 835         if (truncate_xattr_node(inode, page)) {
 836                 f2fs_put_page(page, 1);
 837                 return;
 838         }
 839         /* 0 is possible, after f2fs_new_inode() has failed */
 840         f2fs_bug_on(inode->i_blocks != 0 && inode->i_blocks != 1);
 841         set_new_dnode(&dn, inode, page, page, ino);
 842         truncate_node(&dn);
 843 }
 844
 845 struct page *new_inode_page(struct inode *inode)
 846 {
 847         struct dnode_of_data dn;
 848
 849         /* allocate inode page for new inode */
 850         set_new_dnode(&dn, inode, NULL, NULL, inode->i_ino);
 851
 852         /* caller should f2fs_put_page(page, 1); */
 853         return new_node_page(&dn, 0, NULL);
 854 }
 855
 856 struct page *new_node_page(struct dnode_of_data *dn,
 857                                 unsigned int ofs, struct page *ipage)
 858 {
 859         struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
 860         struct node_info old_ni, new_ni;
 861         struct page *page;
 862         int err;
 863
 864         if (unlikely(is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC)))
 865                 return ERR_PTR(-EPERM);
 866
 867         page = grab_cache_page(NODE_MAPPING(sbi), dn->nid);
 868         if (!page)
 869                 return ERR_PTR(-ENOMEM);
 870
 871         if (unlikely(!inc_valid_node_count(sbi, dn->inode))) {
 872                 err = -ENOSPC;
 873                 goto fail;
 874         }
 875
 876         get_node_info(sbi, dn->nid, &old_ni);
 877
 878         /* Reinitialize old_ni with new node page */
 879         f2fs_bug_on(old_ni.blk_addr != NULL_ADDR);
 880         new_ni = old_ni;
 881         new_ni.ino = dn->inode->i_ino;
 882         set_node_addr(sbi, &new_ni, NEW_ADDR, false);
 883
 884         f2fs_wait_on_page_writeback(page, NODE);
 885         fill_node_footer(page, dn->nid, dn->inode->i_ino, ofs, true);
 886         set_cold_node(dn->inode, page);
 887         SetPageUptodate(page);
 888         set_page_dirty(page);
 889
 890         if (f2fs_has_xattr_block(ofs))
 891                 F2FS_I(dn->inode)->i_xattr_nid = dn->nid;
 892
 893         dn->node_page = page;
 894         if (ipage)
 895                 update_inode(dn->inode, ipage);
 896         else
 897                 sync_inode_page(dn);
 898         if (ofs == 0)
 899                 inc_valid_inode_count(sbi);
 900
 901         return page;
 902
 903 fail:
 904         clear_node_page_dirty(page);
 905         f2fs_put_page(page, 1);
 906         return ERR_PTR(err);
 907 }
 908
 909 /*
 910  * Caller should do after getting the following values.
 911  * 0: f2fs_put_page(page, 0)
 912  * LOCKED_PAGE: f2fs_put_page(page, 1)
 913  * error: nothing
 914  */
 915 static int read_node_page(struct page *page, int rw)
 916 {
 917         struct f2fs_sb_info *sbi = F2FS_SB(page->mapping->host->i_sb);
 918         struct node_info ni;
 919
 920         get_node_info(sbi, page->index, &ni);
 921
 922         if (unlikely(ni.blk_addr == NULL_ADDR)) {
 923                 f2fs_put_page(page, 1);
 924                 return -ENOENT;
 925         }
 926
 927         if (PageUptodate(page))
 928                 return LOCKED_PAGE;
 929
 930         return f2fs_submit_page_bio(sbi, page, ni.blk_addr, rw);
 931 }
 932
 933 /*
 934  * Readahead a node page
 935  */
 936 void ra_node_page(struct f2fs_sb_info *sbi, nid_t nid)
 937 {
 938         struct page *apage;
 939         int err;
 940
 941         apage = find_get_page(NODE_MAPPING(sbi), nid);
 942         if (apage && PageUptodate(apage)) {
 943                 f2fs_put_page(apage, 0);
 944                 return;
 945         }
 946         f2fs_put_page(apage, 0);
 947
 948         apage = grab_cache_page(NODE_MAPPING(sbi), nid);
 949         if (!apage)
 950                 return;
 951
 952         err = read_node_page(apage, READA);
 953         if (err == 0)
 954                 f2fs_put_page(apage, 0);
 955         else if (err == LOCKED_PAGE)
 956                 f2fs_put_page(apage, 1);
 957 }
 958
 959 struct page *get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid)
 960 {
 961         struct page *page;
 962         int err;
 963 repeat:
 964         page = grab_cache_page(NODE_MAPPING(sbi), nid);
 965         if (!page)
 966                 return ERR_PTR(-ENOMEM);
 967
 968         err = read_node_page(page, READ_SYNC);
 969         if (err < 0)
 970                 return ERR_PTR(err);
 971         else if (err == LOCKED_PAGE)
 972                 goto got_it;
 973
 974         lock_page(page);
 975         if (unlikely(!PageUptodate(page) || nid != nid_of_node(page))) {
 976                 f2fs_put_page(page, 1);
 977                 return ERR_PTR(-EIO);
 978         }
 979         if (unlikely(page->mapping != NODE_MAPPING(sbi))) {
 980                 f2fs_put_page(page, 1);
 981                 goto repeat;
 982         }
 983 got_it:
 984         return page;
 985 }
 986
 987 /*
 988  * Return a locked page for the desired node page.
 989  * And, readahead MAX_RA_NODE number of node pages.
 990  */
 991 struct page *get_node_page_ra(struct page *parent, int start)
 992 {
 993         struct f2fs_sb_info *sbi = F2FS_SB(parent->mapping->host->i_sb);
 994         struct blk_plug plug;
 995         struct page *page;
 996         int err, i, end;
 997         nid_t nid;
 998
 999         /* First, try getting the desired direct node. */
1000         nid = get_nid(parent, start, false);
1001         if (!nid)
1002                 return ERR_PTR(-ENOENT);
1003 repeat:
1004         page = grab_cache_page(NODE_MAPPING(sbi), nid);
1005         if (!page)
1006                 return ERR_PTR(-ENOMEM);
1007
1008         err = read_node_page(page, READ_SYNC);
1009         if (err < 0)
1010                 return ERR_PTR(err);
1011         else if (err == LOCKED_PAGE)
1012                 goto page_hit;
1013
1014         blk_start_plug(&plug);
1015
1016         /* Then, try readahead for siblings of the desired node */
1017         end = start + MAX_RA_NODE;
1018         end = min(end, NIDS_PER_BLOCK);
1019         for (i = start + 1; i < end; i++) {
1020                 nid = get_nid(parent, i, false);
1021                 if (!nid)
1022                         continue;
1023                 ra_node_page(sbi, nid);
1024         }
1025
1026         blk_finish_plug(&plug);
1027
1028         lock_page(page);
1029         if (unlikely(page->mapping != NODE_MAPPING(sbi))) {
1030                 f2fs_put_page(page, 1);
1031                 goto repeat;
1032         }
1033 page_hit:
1034         if (unlikely(!PageUptodate(page))) {
1035                 f2fs_put_page(page, 1);
1036                 return ERR_PTR(-EIO);
1037         }
1038         return page;
1039 }
1040
1041 void sync_inode_page(struct dnode_of_data *dn)
1042 {
1043         if (IS_INODE(dn->node_page) || dn->inode_page == dn->node_page) {
1044                 update_inode(dn->inode, dn->node_page);
1045         } else if (dn->inode_page) {
1046                 if (!dn->inode_page_locked)
1047                         lock_page(dn->inode_page);
1048                 update_inode(dn->inode, dn->inode_page);
1049                 if (!dn->inode_page_locked)
1050                         unlock_page(dn->inode_page);
1051         } else {
1052                 update_inode_page(dn->inode);
1053         }
1054 }
1055
1056 int sync_node_pages(struct f2fs_sb_info *sbi, nid_t ino,
1057                                         struct writeback_control *wbc)
1058 {
1059         pgoff_t index, end;
1060         struct pagevec pvec;
1061         int step = ino ? 2 : 0;
1062         int nwritten = 0, wrote = 0;
1063
1064         pagevec_init(&pvec, 0);
1065
1066 next_step:
1067         index = 0;
1068         end = LONG_MAX;
1069
1070         while (index <= end) {
1071                 int i, nr_pages;
1072                 nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index,
1073                                 PAGECACHE_TAG_DIRTY,
1074                                 min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
1075                 if (nr_pages == 0)
1076                         break;
1077
1078                 for (i = 0; i < nr_pages; i++) {
1079                         struct page *page = pvec.pages[i];
1080
1081                         /*
1082                          * flushing sequence with step:
1083                          * 0. indirect nodes
1084                          * 1. dentry dnodes
1085                          * 2. file dnodes
1086                          */
1087                         if (step == 0 && IS_DNODE(page))
1088                                 continue;
1089                         if (step == 1 && (!IS_DNODE(page) ||
1090                                                 is_cold_node(page)))
1091                                 continue;
1092                         if (step == 2 && (!IS_DNODE(page) ||
1093                                                 !is_cold_node(page)))
1094                                 continue;
1095
1096                         /*
1097                          * If an fsync mode,
1098                          * we should not skip writing node pages.
1099                          */
1100                         if (ino && ino_of_node(page) == ino)
1101                                 lock_page(page);
1102                         else if (!trylock_page(page))
1103                                 continue;
1104
1105                         if (unlikely(page->mapping != NODE_MAPPING(sbi))) {
1106 continue_unlock:
1107                                 unlock_page(page);
1108                                 continue;
1109                         }
1110                         if (ino && ino_of_node(page) != ino)
1111                                 goto continue_unlock;
1112
1113                         if (!PageDirty(page)) {
1114                                 /* someone wrote it for us */
1115                                 goto continue_unlock;
1116                         }
1117
1118                         if (!clear_page_dirty_for_io(page))
1119                                 goto continue_unlock;
1120
1121                         /* called by fsync() */
1122                         if (ino && IS_DNODE(page)) {
1123                                 int mark = !is_checkpointed_node(sbi, ino);
1124                                 set_fsync_mark(page, 1);
1125                                 if (IS_INODE(page))
1126                                         set_dentry_mark(page, mark);
1127                                 nwritten++;
1128                         } else {
1129                                 set_fsync_mark(page, 0);
1130                                 set_dentry_mark(page, 0);
1131                         }
1132
1133                         if (NODE_MAPPING(sbi)->a_ops->writepage(page, wbc))
1134                                 unlock_page(page);
1135                         else
1136                                 wrote++;
1137
1138                         if (--wbc->nr_to_write == 0)
1139                                 break;
1140                 }
1141                 pagevec_release(&pvec);
1142                 cond_resched();
1143
1144                 if (wbc->nr_to_write == 0) {
1145                         step = 2;
1146                         break;
1147                 }
1148         }
1149
1150         if (step < 2) {
1151                 step++;
1152                 goto next_step;
1153         }
1154
1155         if (wrote)
1156                 f2fs_submit_merged_bio(sbi, NODE, WRITE);
1157         return nwritten;
1158 }
1159
1160 int wait_on_node_pages_writeback(struct f2fs_sb_info *sbi, nid_t ino)
1161 {
1162         pgoff_t index = 0, end = LONG_MAX;
1163         struct pagevec pvec;
1164         int ret2 = 0, ret = 0;
1165
1166         pagevec_init(&pvec, 0);
1167
1168         while (index <= end) {
1169                 int i, nr_pages;
1170                 nr_pages = pagevec_lookup_tag(&pvec, NODE_MAPPING(sbi), &index,
1171                                 PAGECACHE_TAG_WRITEBACK,
1172                                 min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
1173                 if (nr_pages == 0)
1174                         break;
1175
1176                 for (i = 0; i < nr_pages; i++) {
1177                         struct page *page = pvec.pages[i];
1178
1179                         /* until radix tree lookup accepts end_index */
1180                         if (unlikely(page->index > end))
1181                                 continue;
1182
1183                         if (ino && ino_of_node(page) == ino) {
1184                                 f2fs_wait_on_page_writeback(page, NODE);
1185                                 if (TestClearPageError(page))
1186                                         ret = -EIO;
1187                         }
1188                 }
1189                 pagevec_release(&pvec);
1190                 cond_resched();
1191         }
1192
1193         if (unlikely(test_and_clear_bit(AS_ENOSPC, &NODE_MAPPING(sbi)->flags)))
1194                 ret2 = -ENOSPC;
1195         if (unlikely(test_and_clear_bit(AS_EIO, &NODE_MAPPING(sbi)->flags)))
1196                 ret2 = -EIO;
1197         if (!ret)
1198                 ret = ret2;
1199         return ret;
1200 }
1201
1202 static int f2fs_write_node_page(struct page *page,
1203                                 struct writeback_control *wbc)
1204 {
1205         struct f2fs_sb_info *sbi = F2FS_SB(page->mapping->host->i_sb);
1206         nid_t nid;
1207         block_t new_addr;
1208         struct node_info ni;
1209         struct f2fs_io_info fio = {
1210                 .type = NODE,
1211                 .rw = (wbc->sync_mode == WB_SYNC_ALL) ? WRITE_SYNC : WRITE,
1212         };
1213
1214         trace_f2fs_writepage(page, NODE);
1215
1216         if (unlikely(sbi->por_doing))
1217                 goto redirty_out;
1218         if (unlikely(f2fs_cp_error(sbi)))
1219                 goto redirty_out;
1220
1221         f2fs_wait_on_page_writeback(page, NODE);
1222
1223         /* get old block addr of this node page */
1224         nid = nid_of_node(page);
1225         f2fs_bug_on(page->index != nid);
1226
1227         get_node_info(sbi, nid, &ni);
1228
1229         /* This page is already truncated */
1230         if (unlikely(ni.blk_addr == NULL_ADDR)) {
1231                 dec_page_count(sbi, F2FS_DIRTY_NODES);
1232                 unlock_page(page);
1233                 return 0;
1234         }
1235
1236         if (wbc->for_reclaim)
1237                 goto redirty_out;
1238
1239         down_read(&sbi->node_write);
1240         set_page_writeback(page);
1241         write_node_page(sbi, page, &fio, nid, ni.blk_addr, &new_addr);
1242         set_node_addr(sbi, &ni, new_addr, is_fsync_dnode(page));
1243         dec_page_count(sbi, F2FS_DIRTY_NODES);
1244         up_read(&sbi->node_write);
1245         unlock_page(page);
1246         return 0;
1247
1248 redirty_out:
1249         redirty_page_for_writepage(wbc, page);
1250         return AOP_WRITEPAGE_ACTIVATE;
1251 }
1252
1253 static int f2fs_write_node_pages(struct address_space *mapping,
1254                             struct writeback_control *wbc)
1255 {
1256         struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
1257         long diff;
1258
1259         trace_f2fs_writepages(mapping->host, wbc, NODE);
1260
1261         /* balancing f2fs's metadata in background */
1262         f2fs_balance_fs_bg(sbi);
1263
1264         /* collect a number of dirty node pages and write together */
1265         if (get_pages(sbi, F2FS_DIRTY_NODES) < nr_pages_to_skip(sbi, NODE))
1266                 goto skip_write;
1267
1268         diff = nr_pages_to_write(sbi, NODE, wbc);
1269         wbc->sync_mode = WB_SYNC_NONE;
1270         sync_node_pages(sbi, 0, wbc);
1271         wbc->nr_to_write = max((long)0, wbc->nr_to_write - diff);
1272         return 0;
1273
1274 skip_write:
1275         wbc->pages_skipped += get_pages(sbi, F2FS_DIRTY_NODES);
1276         return 0;
1277 }
1278
1279 static int f2fs_set_node_page_dirty(struct page *page)
1280 {
1281         struct address_space *mapping = page->mapping;
1282         struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
1283
1284         trace_f2fs_set_page_dirty(page, NODE);
1285
1286         SetPageUptodate(page);
1287         if (!PageDirty(page)) {
1288                 __set_page_dirty_nobuffers(page);
1289                 inc_page_count(sbi, F2FS_DIRTY_NODES);
1290                 SetPagePrivate(page);
1291                 return 1;
1292         }
1293         return 0;
1294 }
1295
1296 static void f2fs_invalidate_node_page(struct page *page, unsigned int offset,
1297                                       unsigned int length)
1298 {
1299         struct inode *inode = page->mapping->host;
1300         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
1301         if (PageDirty(page))
1302                 dec_page_count(sbi, F2FS_DIRTY_NODES);
1303         ClearPagePrivate(page);
1304 }
1305
1306 static int f2fs_release_node_page(struct page *page, gfp_t wait)
1307 {
1308         ClearPagePrivate(page);
1309         return 1;
1310 }
1311
1312 /*
1313  * Structure of the f2fs node operations
1314  */
1315 const struct address_space_operations f2fs_node_aops = {
1316         .writepage      = f2fs_write_node_page,
1317         .writepages     = f2fs_write_node_pages,
1318         .set_page_dirty = f2fs_set_node_page_dirty,
1319         .invalidatepage = f2fs_invalidate_node_page,
1320         .releasepage    = f2fs_release_node_page,
1321 };
1322
1323 static struct free_nid *__lookup_free_nid_list(struct f2fs_nm_info *nm_i,
1324                                                 nid_t n)
1325 {
1326         return radix_tree_lookup(&nm_i->free_nid_root, n);
1327 }
1328
1329 static void __del_from_free_nid_list(struct f2fs_nm_info *nm_i,
1330                                                 struct free_nid *i)
1331 {
1332         list_del(&i->list);
1333         radix_tree_delete(&nm_i->free_nid_root, i->nid);
1334 }
1335
1336 static int add_free_nid(struct f2fs_sb_info *sbi, nid_t nid, bool build)
1337 {
1338         struct f2fs_nm_info *nm_i = NM_I(sbi);
1339         struct free_nid *i;
1340         struct nat_entry *ne;
1341         bool allocated = false;
1342
1343         if (!available_free_memory(sbi, FREE_NIDS))
1344                 return -1;
1345
1346         /* 0 nid should not be used */
1347         if (unlikely(nid == 0))
1348                 return 0;
1349
1350         if (build) {
1351                 /* do not add allocated nids */
1352                 read_lock(&nm_i->nat_tree_lock);
1353                 ne = __lookup_nat_cache(nm_i, nid);
1354                 if (ne &&
1355                         (!ne->checkpointed || nat_get_blkaddr(ne) != NULL_ADDR))
1356                         allocated = true;
1357                 read_unlock(&nm_i->nat_tree_lock);
1358                 if (allocated)
1359                         return 0;
1360         }
1361
1362         i = f2fs_kmem_cache_alloc(free_nid_slab, GFP_NOFS);
1363         i->nid = nid;
1364         i->state = NID_NEW;
1365
1366         spin_lock(&nm_i->free_nid_list_lock);
1367         if (radix_tree_insert(&nm_i->free_nid_root, i->nid, i)) {
1368                 spin_unlock(&nm_i->free_nid_list_lock);
1369                 kmem_cache_free(free_nid_slab, i);
1370                 return 0;
1371         }
1372         list_add_tail(&i->list, &nm_i->free_nid_list);
1373         nm_i->fcnt++;
1374         spin_unlock(&nm_i->free_nid_list_lock);
1375         return 1;
1376 }
1377
1378 static void remove_free_nid(struct f2fs_nm_info *nm_i, nid_t nid)
1379 {
1380         struct free_nid *i;
1381         bool need_free = false;
1382
1383         spin_lock(&nm_i->free_nid_list_lock);
1384         i = __lookup_free_nid_list(nm_i, nid);
1385         if (i && i->state == NID_NEW) {
1386                 __del_from_free_nid_list(nm_i, i);
1387                 nm_i->fcnt--;
1388                 need_free = true;
1389         }
1390         spin_unlock(&nm_i->free_nid_list_lock);
1391
1392         if (need_free)
1393                 kmem_cache_free(free_nid_slab, i);
1394 }
1395
1396 static void scan_nat_page(struct f2fs_sb_info *sbi,
1397                         struct page *nat_page, nid_t start_nid)
1398 {
1399         struct f2fs_nm_info *nm_i = NM_I(sbi);
1400         struct f2fs_nat_block *nat_blk = page_address(nat_page);
1401         block_t blk_addr;
1402         int i;
1403
1404         i = start_nid % NAT_ENTRY_PER_BLOCK;
1405
1406         for (; i < NAT_ENTRY_PER_BLOCK; i++, start_nid++) {
1407
1408                 if (unlikely(start_nid >= nm_i->max_nid))
1409                         break;
1410
1411                 blk_addr = le32_to_cpu(nat_blk->entries[i].block_addr);
1412                 f2fs_bug_on(blk_addr == NEW_ADDR);
1413                 if (blk_addr == NULL_ADDR) {
1414                         if (add_free_nid(sbi, start_nid, true) < 0)
1415                                 break;
1416                 }
1417         }
1418 }
1419
1420 static void build_free_nids(struct f2fs_sb_info *sbi)
1421 {
1422         struct f2fs_nm_info *nm_i = NM_I(sbi);
1423         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_HOT_DATA);
1424         struct f2fs_summary_block *sum = curseg->sum_blk;
1425         int i = 0;
1426         nid_t nid = nm_i->next_scan_nid;
1427
1428         /* Enough entries */
1429         if (nm_i->fcnt > NAT_ENTRY_PER_BLOCK)
1430                 return;
1431
1432         /* readahead nat pages to be scanned */
1433         ra_meta_pages(sbi, NAT_BLOCK_OFFSET(nid), FREE_NID_PAGES, META_NAT);
1434
1435         while (1) {
1436                 struct page *page = get_current_nat_page(sbi, nid);
1437
1438                 scan_nat_page(sbi, page, nid);
1439                 f2fs_put_page(page, 1);
1440
1441                 nid += (NAT_ENTRY_PER_BLOCK - (nid % NAT_ENTRY_PER_BLOCK));
1442                 if (unlikely(nid >= nm_i->max_nid))
1443                         nid = 0;
1444
1445                 if (i++ == FREE_NID_PAGES)
1446                         break;
1447         }
1448
1449         /* go to the next free nat pages to find free nids abundantly */
1450         nm_i->next_scan_nid = nid;
1451
1452         /* find free nids from current sum_pages */
1453         mutex_lock(&curseg->curseg_mutex);
1454         for (i = 0; i < nats_in_cursum(sum); i++) {
1455                 block_t addr = le32_to_cpu(nat_in_journal(sum, i).block_addr);
1456                 nid = le32_to_cpu(nid_in_journal(sum, i));
1457                 if (addr == NULL_ADDR)
1458                         add_free_nid(sbi, nid, true);
1459                 else
1460                         remove_free_nid(nm_i, nid);
1461         }
1462         mutex_unlock(&curseg->curseg_mutex);
1463 }
1464
1465 /*
1466  * If this function returns success, caller can obtain a new nid
1467  * from second parameter of this function.
1468  * The returned nid could be used ino as well as nid when inode is created.
1469  */
1470 bool alloc_nid(struct f2fs_sb_info *sbi, nid_t *nid)
1471 {
1472         struct f2fs_nm_info *nm_i = NM_I(sbi);
1473         struct free_nid *i = NULL;
1474 retry:
1475         if (unlikely(sbi->total_valid_node_count + 1 > nm_i->available_nids))
1476                 return false;
1477
1478         spin_lock(&nm_i->free_nid_list_lock);
1479
1480         /* We should not use stale free nids created by build_free_nids */
1481         if (nm_i->fcnt && !on_build_free_nids(nm_i)) {
1482                 f2fs_bug_on(list_empty(&nm_i->free_nid_list));
1483                 list_for_each_entry(i, &nm_i->free_nid_list, list)
1484                         if (i->state == NID_NEW)
1485                                 break;
1486
1487                 f2fs_bug_on(i->state != NID_NEW);
1488                 *nid = i->nid;
1489                 i->state = NID_ALLOC;
1490                 nm_i->fcnt--;
1491                 spin_unlock(&nm_i->free_nid_list_lock);
1492                 return true;
1493         }
1494         spin_unlock(&nm_i->free_nid_list_lock);
1495
1496         /* Let's scan nat pages and its caches to get free nids */
1497         mutex_lock(&nm_i->build_lock);
1498         build_free_nids(sbi);
1499         mutex_unlock(&nm_i->build_lock);
1500         goto retry;
1501 }
1502
1503 /*
1504  * alloc_nid() should be called prior to this function.
1505  */
1506 void alloc_nid_done(struct f2fs_sb_info *sbi, nid_t nid)
1507 {
1508         struct f2fs_nm_info *nm_i = NM_I(sbi);
1509         struct free_nid *i;
1510
1511         spin_lock(&nm_i->free_nid_list_lock);
1512         i = __lookup_free_nid_list(nm_i, nid);
1513         f2fs_bug_on(!i || i->state != NID_ALLOC);
1514         __del_from_free_nid_list(nm_i, i);
1515         spin_unlock(&nm_i->free_nid_list_lock);
1516
1517         kmem_cache_free(free_nid_slab, i);
1518 }
1519
1520 /*
1521  * alloc_nid() should be called prior to this function.
1522  */
1523 void alloc_nid_failed(struct f2fs_sb_info *sbi, nid_t nid)
1524 {
1525         struct f2fs_nm_info *nm_i = NM_I(sbi);
1526         struct free_nid *i;
1527         bool need_free = false;
1528
1529         if (!nid)
1530                 return;
1531
1532         spin_lock(&nm_i->free_nid_list_lock);
1533         i = __lookup_free_nid_list(nm_i, nid);
1534         f2fs_bug_on(!i || i->state != NID_ALLOC);
1535         if (!available_free_memory(sbi, FREE_NIDS)) {
1536                 __del_from_free_nid_list(nm_i, i);
1537                 need_free = true;
1538         } else {
1539                 i->state = NID_NEW;
1540                 nm_i->fcnt++;
1541         }
1542         spin_unlock(&nm_i->free_nid_list_lock);
1543
1544         if (need_free)
1545                 kmem_cache_free(free_nid_slab, i);
1546 }
1547
1548 void recover_inline_xattr(struct inode *inode, struct page *page)
1549 {
1550         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
1551         void *src_addr, *dst_addr;
1552         size_t inline_size;
1553         struct page *ipage;
1554         struct f2fs_inode *ri;
1555
1556         ipage = get_node_page(sbi, inode->i_ino);
1557         f2fs_bug_on(IS_ERR(ipage));
1558
1559         ri = F2FS_INODE(page);
1560         if (!(ri->i_inline & F2FS_INLINE_XATTR)) {
1561                 clear_inode_flag(F2FS_I(inode), FI_INLINE_XATTR);
1562                 goto update_inode;
1563         }
1564
1565         dst_addr = inline_xattr_addr(ipage);
1566         src_addr = inline_xattr_addr(page);
1567         inline_size = inline_xattr_size(inode);
1568
1569         f2fs_wait_on_page_writeback(ipage, NODE);
1570         memcpy(dst_addr, src_addr, inline_size);
1571 update_inode:
1572         update_inode(inode, ipage);
1573         f2fs_put_page(ipage, 1);
1574 }
1575
1576 void recover_xattr_data(struct inode *inode, struct page *page, block_t blkaddr)
1577 {
1578         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
1579         nid_t prev_xnid = F2FS_I(inode)->i_xattr_nid;
1580         nid_t new_xnid = nid_of_node(page);
1581         struct node_info ni;
1582
1583         /* 1: invalidate the previous xattr nid */
1584         if (!prev_xnid)
1585                 goto recover_xnid;
1586
1587         /* Deallocate node address */
1588         get_node_info(sbi, prev_xnid, &ni);
1589         f2fs_bug_on(ni.blk_addr == NULL_ADDR);
1590         invalidate_blocks(sbi, ni.blk_addr);
1591         dec_valid_node_count(sbi, inode);
1592         set_node_addr(sbi, &ni, NULL_ADDR, false);
1593
1594 recover_xnid:
1595         /* 2: allocate new xattr nid */
1596         if (unlikely(!inc_valid_node_count(sbi, inode)))
1597                 f2fs_bug_on(1);
1598
1599         remove_free_nid(NM_I(sbi), new_xnid);
1600         get_node_info(sbi, new_xnid, &ni);
1601         ni.ino = inode->i_ino;
1602         set_node_addr(sbi, &ni, NEW_ADDR, false);
1603         F2FS_I(inode)->i_xattr_nid = new_xnid;
1604
1605         /* 3: update xattr blkaddr */
1606         refresh_sit_entry(sbi, NEW_ADDR, blkaddr);
1607         set_node_addr(sbi, &ni, blkaddr, false);
1608
1609         update_inode_page(inode);
1610 }
1611
1612 int recover_inode_page(struct f2fs_sb_info *sbi, struct page *page)
1613 {
1614         struct f2fs_inode *src, *dst;
1615         nid_t ino = ino_of_node(page);
1616         struct node_info old_ni, new_ni;
1617         struct page *ipage;
1618
1619         get_node_info(sbi, ino, &old_ni);
1620
1621         if (unlikely(old_ni.blk_addr != NULL_ADDR))
1622                 return -EINVAL;
1623
1624         ipage = grab_cache_page(NODE_MAPPING(sbi), ino);
1625         if (!ipage)
1626                 return -ENOMEM;
1627
1628         /* Should not use this inode from free nid list */
1629         remove_free_nid(NM_I(sbi), ino);
1630
1631         SetPageUptodate(ipage);
1632         fill_node_footer(ipage, ino, ino, 0, true);
1633
1634         src = F2FS_INODE(page);
1635         dst = F2FS_INODE(ipage);
1636
1637         memcpy(dst, src, (unsigned long)&src->i_ext - (unsigned long)src);
1638         dst->i_size = 0;
1639         dst->i_blocks = cpu_to_le64(1);
1640         dst->i_links = cpu_to_le32(1);
1641         dst->i_xattr_nid = 0;
1642         dst->i_inline = src->i_inline & F2FS_INLINE_XATTR;
1643
1644         new_ni = old_ni;
1645         new_ni.ino = ino;
1646
1647         if (unlikely(!inc_valid_node_count(sbi, NULL)))
1648                 WARN_ON(1);
1649         set_node_addr(sbi, &new_ni, NEW_ADDR, false);
1650         inc_valid_inode_count(sbi);
1651         set_page_dirty(ipage);
1652         f2fs_put_page(ipage, 1);
1653         return 0;
1654 }
1655
1656 /*
1657  * ra_sum_pages() merge contiguous pages into one bio and submit.
1658  * these pre-read pages are allocated in bd_inode's mapping tree.
1659  */
1660 static int ra_sum_pages(struct f2fs_sb_info *sbi, struct page **pages,
1661                                 int start, int nrpages)
1662 {
1663         struct inode *inode = sbi->sb->s_bdev->bd_inode;
1664         struct address_space *mapping = inode->i_mapping;
1665         int i, page_idx = start;
1666         struct f2fs_io_info fio = {
1667                 .type = META,
1668                 .rw = READ_SYNC | REQ_META | REQ_PRIO
1669         };
1670
1671         for (i = 0; page_idx < start + nrpages; page_idx++, i++) {
1672                 /* alloc page in bd_inode for reading node summary info */
1673                 pages[i] = grab_cache_page(mapping, page_idx);
1674                 if (!pages[i])
1675                         break;
1676                 f2fs_submit_page_mbio(sbi, pages[i], page_idx, &fio);
1677         }
1678
1679         f2fs_submit_merged_bio(sbi, META, READ);
1680         return i;
1681 }
1682
1683 int restore_node_summary(struct f2fs_sb_info *sbi,
1684                         unsigned int segno, struct f2fs_summary_block *sum)
1685 {
1686         struct f2fs_node *rn;
1687         struct f2fs_summary *sum_entry;
1688         struct inode *inode = sbi->sb->s_bdev->bd_inode;
1689         block_t addr;
1690         int bio_blocks = MAX_BIO_BLOCKS(max_hw_blocks(sbi));
1691         struct page *pages[bio_blocks];
1692         int i, idx, last_offset, nrpages, err = 0;
1693
1694         /* scan the node segment */
1695         last_offset = sbi->blocks_per_seg;
1696         addr = START_BLOCK(sbi, segno);
1697         sum_entry = &sum->entries[0];
1698
1699         for (i = 0; !err && i < last_offset; i += nrpages, addr += nrpages) {
1700                 nrpages = min(last_offset - i, bio_blocks);
1701
1702                 /* readahead node pages */
1703                 nrpages = ra_sum_pages(sbi, pages, addr, nrpages);
1704                 if (!nrpages)
1705                         return -ENOMEM;
1706
1707                 for (idx = 0; idx < nrpages; idx++) {
1708                         if (err)
1709                                 goto skip;
1710
1711                         lock_page(pages[idx]);
1712                         if (unlikely(!PageUptodate(pages[idx]))) {
1713                                 err = -EIO;
1714                         } else {
1715                                 rn = F2FS_NODE(pages[idx]);
1716                                 sum_entry->nid = rn->footer.nid;
1717                                 sum_entry->version = 0;
1718                                 sum_entry->ofs_in_node = 0;
1719                                 sum_entry++;
1720                         }
1721                         unlock_page(pages[idx]);
1722 skip:
1723                         page_cache_release(pages[idx]);
1724                 }
1725
1726                 invalidate_mapping_pages(inode->i_mapping, addr,
1727                                                         addr + nrpages);
1728         }
1729         return err;
1730 }
1731
1732 static struct nat_entry_set *grab_nat_entry_set(void)
1733 {
1734         struct nat_entry_set *nes =
1735                         f2fs_kmem_cache_alloc(nat_entry_set_slab, GFP_ATOMIC);
1736
1737         nes->entry_cnt = 0;
1738         INIT_LIST_HEAD(&nes->set_list);
1739         INIT_LIST_HEAD(&nes->entry_list);
1740         return nes;
1741 }
1742
1743 static void release_nat_entry_set(struct nat_entry_set *nes,
1744                                                 struct f2fs_nm_info *nm_i)
1745 {
1746         f2fs_bug_on(!list_empty(&nes->entry_list));
1747
1748         nm_i->dirty_nat_cnt -= nes->entry_cnt;
1749         list_del(&nes->set_list);
1750         kmem_cache_free(nat_entry_set_slab, nes);
1751 }
1752
1753 static void adjust_nat_entry_set(struct nat_entry_set *nes,
1754                                                 struct list_head *head)
1755 {
1756         struct nat_entry_set *next = nes;
1757
1758         if (list_is_last(&nes->set_list, head))
1759                 return;
1760
1761         list_for_each_entry_continue(next, head, set_list)
1762                 if (nes->entry_cnt <= next->entry_cnt)
1763                         break;
1764
1765         list_move_tail(&nes->set_list, &next->set_list);
1766 }
1767
1768 static void add_nat_entry(struct nat_entry *ne, struct list_head *head)
1769 {
1770         struct nat_entry_set *nes;
1771         nid_t start_nid = START_NID(ne->ni.nid);
1772
1773         list_for_each_entry(nes, head, set_list) {
1774                 if (nes->start_nid == start_nid) {
1775                         list_move_tail(&ne->list, &nes->entry_list);
1776                         nes->entry_cnt++;
1777                         adjust_nat_entry_set(nes, head);
1778                         return;
1779                 }
1780         }
1781
1782         nes = grab_nat_entry_set();
1783
1784         nes->start_nid = start_nid;
1785         list_move_tail(&ne->list, &nes->entry_list);
1786         nes->entry_cnt++;
1787         list_add(&nes->set_list, head);
1788 }
1789
1790 static void merge_nats_in_set(struct f2fs_sb_info *sbi)
1791 {
1792         struct f2fs_nm_info *nm_i = NM_I(sbi);
1793         struct list_head *dirty_list = &nm_i->dirty_nat_entries;
1794         struct list_head *set_list = &nm_i->nat_entry_set;
1795         struct nat_entry *ne, *tmp;
1796
1797         write_lock(&nm_i->nat_tree_lock);
1798         list_for_each_entry_safe(ne, tmp, dirty_list, list) {
1799                 if (nat_get_blkaddr(ne) == NEW_ADDR)
1800                         continue;
1801                 add_nat_entry(ne, set_list);
1802                 nm_i->dirty_nat_cnt++;
1803         }
1804         write_unlock(&nm_i->nat_tree_lock);
1805 }
1806
1807 static bool __has_cursum_space(struct f2fs_summary_block *sum, int size)
1808 {
1809         if (nats_in_cursum(sum) + size <= NAT_JOURNAL_ENTRIES)
1810                 return true;
1811         else
1812                 return false;
1813 }
1814
1815 static void remove_nats_in_journal(struct f2fs_sb_info *sbi)
1816 {
1817         struct f2fs_nm_info *nm_i = NM_I(sbi);
1818         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_HOT_DATA);
1819         struct f2fs_summary_block *sum = curseg->sum_blk;
1820         int i;
1821
1822         mutex_lock(&curseg->curseg_mutex);
1823         for (i = 0; i < nats_in_cursum(sum); i++) {
1824                 struct nat_entry *ne;
1825                 struct f2fs_nat_entry raw_ne;
1826                 nid_t nid = le32_to_cpu(nid_in_journal(sum, i));
1827
1828                 raw_ne = nat_in_journal(sum, i);
1829 retry:
1830                 write_lock(&nm_i->nat_tree_lock);
1831                 ne = __lookup_nat_cache(nm_i, nid);
1832                 if (ne)
1833                         goto found;
1834
1835                 ne = grab_nat_entry(nm_i, nid);
1836                 if (!ne) {
1837                         write_unlock(&nm_i->nat_tree_lock);
1838                         goto retry;
1839                 }
1840                 node_info_from_raw_nat(&ne->ni, &raw_ne);
1841 found:
1842                 __set_nat_cache_dirty(nm_i, ne);
1843                 write_unlock(&nm_i->nat_tree_lock);
1844         }
1845         update_nats_in_cursum(sum, -i);
1846         mutex_unlock(&curseg->curseg_mutex);
1847 }
1848
1849 /*
1850  * This function is called during the checkpointing process.
1851  */
1852 void flush_nat_entries(struct f2fs_sb_info *sbi)
1853 {
1854         struct f2fs_nm_info *nm_i = NM_I(sbi);
1855         struct curseg_info *curseg = CURSEG_I(sbi, CURSEG_HOT_DATA);
1856         struct f2fs_summary_block *sum = curseg->sum_blk;
1857         struct nat_entry_set *nes, *tmp;
1858         struct list_head *head = &nm_i->nat_entry_set;
1859         bool to_journal = true;
1860
1861         /* merge nat entries of dirty list to nat entry set temporarily */
1862         merge_nats_in_set(sbi);
1863
1864         /*
1865          * if there are no enough space in journal to store dirty nat
1866          * entries, remove all entries from journal and merge them
1867          * into nat entry set.
1868          */
1869         if (!__has_cursum_space(sum, nm_i->dirty_nat_cnt)) {
1870                 remove_nats_in_journal(sbi);
1871
1872                 /*
1873                  * merge nat entries of dirty list to nat entry set temporarily
1874                  */
1875                 merge_nats_in_set(sbi);
1876         }
1877
1878         if (!nm_i->dirty_nat_cnt)
1879                 return;
1880
1881         /*
1882          * there are two steps to flush nat entries:
1883          * #1, flush nat entries to journal in current hot data summary block.
1884          * #2, flush nat entries to nat page.
1885          */
1886         list_for_each_entry_safe(nes, tmp, head, set_list) {
1887                 struct f2fs_nat_block *nat_blk;
1888                 struct nat_entry *ne, *cur;
1889                 struct page *page;
1890                 nid_t start_nid = nes->start_nid;
1891
1892                 if (to_journal && !__has_cursum_space(sum, nes->entry_cnt))
1893                         to_journal = false;
1894
1895                 if (to_journal) {
1896                         mutex_lock(&curseg->curseg_mutex);
1897                 } else {
1898                         page = get_next_nat_page(sbi, start_nid);
1899                         nat_blk = page_address(page);
1900                         f2fs_bug_on(!nat_blk);
1901                 }
1902
1903                 /* flush dirty nats in nat entry set */
1904                 list_for_each_entry_safe(ne, cur, &nes->entry_list, list) {
1905                         struct f2fs_nat_entry *raw_ne;
1906                         nid_t nid = nat_get_nid(ne);
1907                         int offset;
1908
1909                         if (to_journal) {
1910                                 offset = lookup_journal_in_cursum(sum,
1911                                                         NAT_JOURNAL, nid, 1);
1912                                 f2fs_bug_on(offset < 0);
1913                                 raw_ne = &nat_in_journal(sum, offset);
1914                                 nid_in_journal(sum, offset) = cpu_to_le32(nid);
1915                         } else {
1916                                 raw_ne = &nat_blk->entries[nid - start_nid];
1917                         }
1918                         raw_nat_from_node_info(raw_ne, &ne->ni);
1919
1920                         if (nat_get_blkaddr(ne) == NULL_ADDR &&
1921                                 add_free_nid(sbi, nid, false) <= 0) {
1922                                 write_lock(&nm_i->nat_tree_lock);
1923                                 __del_from_nat_cache(nm_i, ne);
1924                                 write_unlock(&nm_i->nat_tree_lock);
1925                         } else {
1926                                 write_lock(&nm_i->nat_tree_lock);
1927                                 __clear_nat_cache_dirty(nm_i, ne);
1928                                 write_unlock(&nm_i->nat_tree_lock);
1929                         }
1930                 }
1931
1932                 if (to_journal)
1933                         mutex_unlock(&curseg->curseg_mutex);
1934                 else
1935                         f2fs_put_page(page, 1);
1936
1937                 release_nat_entry_set(nes, nm_i);
1938         }
1939
1940         f2fs_bug_on(!list_empty(head));
1941         f2fs_bug_on(nm_i->dirty_nat_cnt);
1942 }
1943
1944 static int init_node_manager(struct f2fs_sb_info *sbi)
1945 {
1946         struct f2fs_super_block *sb_raw = F2FS_RAW_SUPER(sbi);
1947         struct f2fs_nm_info *nm_i = NM_I(sbi);
1948         unsigned char *version_bitmap;
1949         unsigned int nat_segs, nat_blocks;
1950
1951         nm_i->nat_blkaddr = le32_to_cpu(sb_raw->nat_blkaddr);
1952
1953         /* segment_count_nat includes pair segment so divide to 2. */
1954         nat_segs = le32_to_cpu(sb_raw->segment_count_nat) >> 1;
1955         nat_blocks = nat_segs << le32_to_cpu(sb_raw->log_blocks_per_seg);
1956
1957         nm_i->max_nid = NAT_ENTRY_PER_BLOCK * nat_blocks;
1958
1959         /* not used nids: 0, node, meta, (and root counted as valid node) */
1960         nm_i->available_nids = nm_i->max_nid - F2FS_RESERVED_NODE_NUM;
1961         nm_i->fcnt = 0;
1962         nm_i->nat_cnt = 0;
1963         nm_i->ram_thresh = DEF_RAM_THRESHOLD;
1964
1965         INIT_RADIX_TREE(&nm_i->free_nid_root, GFP_ATOMIC);
1966         INIT_LIST_HEAD(&nm_i->free_nid_list);
1967         INIT_RADIX_TREE(&nm_i->nat_root, GFP_ATOMIC);
1968         INIT_LIST_HEAD(&nm_i->nat_entries);
1969         INIT_LIST_HEAD(&nm_i->dirty_nat_entries);
1970         INIT_LIST_HEAD(&nm_i->nat_entry_set);
1971
1972         mutex_init(&nm_i->build_lock);
1973         spin_lock_init(&nm_i->free_nid_list_lock);
1974         rwlock_init(&nm_i->nat_tree_lock);
1975
1976         nm_i->next_scan_nid = le32_to_cpu(sbi->ckpt->next_free_nid);
1977         nm_i->bitmap_size = __bitmap_size(sbi, NAT_BITMAP);
1978         version_bitmap = __bitmap_ptr(sbi, NAT_BITMAP);
1979         if (!version_bitmap)
1980                 return -EFAULT;
1981
1982         nm_i->nat_bitmap = kmemdup(version_bitmap, nm_i->bitmap_size,
1983                                         GFP_KERNEL);
1984         if (!nm_i->nat_bitmap)
1985                 return -ENOMEM;
1986         return 0;
1987 }
1988
1989 int build_node_manager(struct f2fs_sb_info *sbi)
1990 {
1991         int err;
1992
1993         sbi->nm_info = kzalloc(sizeof(struct f2fs_nm_info), GFP_KERNEL);
1994         if (!sbi->nm_info)
1995                 return -ENOMEM;
1996
1997         err = init_node_manager(sbi);
1998         if (err)
1999                 return err;
2000
2001         build_free_nids(sbi);
2002         return 0;
2003 }
2004
2005 void destroy_node_manager(struct f2fs_sb_info *sbi)
2006 {
2007         struct f2fs_nm_info *nm_i = NM_I(sbi);
2008         struct free_nid *i, *next_i;
2009         struct nat_entry *natvec[NATVEC_SIZE];
2010         nid_t nid = 0;
2011         unsigned int found;
2012
2013         if (!nm_i)
2014                 return;
2015
2016         /* destroy free nid list */
2017         spin_lock(&nm_i->free_nid_list_lock);
2018         list_for_each_entry_safe(i, next_i, &nm_i->free_nid_list, list) {
2019                 f2fs_bug_on(i->state == NID_ALLOC);
2020                 __del_from_free_nid_list(nm_i, i);
2021                 nm_i->fcnt--;
2022                 spin_unlock(&nm_i->free_nid_list_lock);
2023                 kmem_cache_free(free_nid_slab, i);
2024                 spin_lock(&nm_i->free_nid_list_lock);
2025         }
2026         f2fs_bug_on(nm_i->fcnt);
2027         spin_unlock(&nm_i->free_nid_list_lock);
2028
2029         /* destroy nat cache */
2030         write_lock(&nm_i->nat_tree_lock);
2031         while ((found = __gang_lookup_nat_cache(nm_i,
2032                                         nid, NATVEC_SIZE, natvec))) {
2033                 unsigned idx;
2034                 nid = nat_get_nid(natvec[found - 1]) + 1;
2035                 for (idx = 0; idx < found; idx++)
2036                         __del_from_nat_cache(nm_i, natvec[idx]);
2037         }
2038         f2fs_bug_on(nm_i->nat_cnt);
2039         write_unlock(&nm_i->nat_tree_lock);
2040
2041         kfree(nm_i->nat_bitmap);
2042         sbi->nm_info = NULL;
2043         kfree(nm_i);
2044 }
2045
2046 int __init create_node_manager_caches(void)
2047 {
2048         nat_entry_slab = f2fs_kmem_cache_create("nat_entry",
2049                         sizeof(struct nat_entry));
2050         if (!nat_entry_slab)
2051                 goto fail;
2052
2053         free_nid_slab = f2fs_kmem_cache_create("free_nid",
2054                         sizeof(struct free_nid));
2055         if (!free_nid_slab)
2056                 goto destory_nat_entry;
2057
2058         nat_entry_set_slab = f2fs_kmem_cache_create("nat_entry_set",
2059                         sizeof(struct nat_entry_set));
2060         if (!nat_entry_set_slab)
2061                 goto destory_free_nid;
2062         return 0;
2063
2064 destory_free_nid:
2065         kmem_cache_destroy(free_nid_slab);
2066 destory_nat_entry:
2067         kmem_cache_destroy(nat_entry_slab);
2068 fail:
2069         return -ENOMEM;
2070 }
2071
2072 void destroy_node_manager_caches(void)
2073 {
2074         kmem_cache_destroy(nat_entry_set_slab);
2075         kmem_cache_destroy(free_nid_slab);
2076         kmem_cache_destroy(nat_entry_slab);
2077 }