fs/f2fs/checkpoint.c

   1 /*
   2  * fs/f2fs/checkpoint.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/bio.h>
  13 #include <linux/mpage.h>
  14 #include <linux/writeback.h>
  15 #include <linux/blkdev.h>
  16 #include <linux/f2fs_fs.h>
  17 #include <linux/pagevec.h>
  18 #include <linux/swap.h>
  19
  20 #include "f2fs.h"
  21 #include "node.h"
  22 #include "segment.h"
  23 #include <trace/events/f2fs.h>
  24
  25 static struct kmem_cache *orphan_entry_slab;
  26 static struct kmem_cache *inode_entry_slab;
  27
  28 /*
  29  * We guarantee no failure on the returned page.
  30  */
  31 struct page *grab_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
  32 {
  33         struct address_space *mapping = META_MAPPING(sbi);
  34         struct page *page = NULL;
  35 repeat:
  36         page = grab_cache_page_write_begin(mapping, index, AOP_FLAG_NOFS);
  37         if (!page) {
  38                 cond_resched();
  39                 goto repeat;
  40         }
  41
  42         SetPageUptodate(page);
  43         return page;
  44 }
  45
  46 /*
  47  * We guarantee no failure on the returned page.
  48  */
  49 struct page *get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index)
  50 {
  51         struct address_space *mapping = META_MAPPING(sbi);
  52         struct page *page;
  53 repeat:
  54         page = grab_cache_page(mapping, index);
  55         if (!page) {
  56                 cond_resched();
  57                 goto repeat;
  58         }
  59         if (PageUptodate(page))
  60                 goto out;
  61
  62         if (f2fs_submit_page_bio(sbi, page, index,
  63                                 READ_SYNC | REQ_META | REQ_PRIO))
  64                 goto repeat;
  65
  66         lock_page(page);
  67         if (unlikely(page->mapping != mapping)) {
  68                 f2fs_put_page(page, 1);
  69                 goto repeat;
  70         }
  71 out:
  72         mark_page_accessed(page);
  73         return page;
  74 }
  75
  76 inline int get_max_meta_blks(struct f2fs_sb_info *sbi, int type)
  77 {
  78         switch (type) {
  79         case META_NAT:
  80                 return NM_I(sbi)->max_nid / NAT_ENTRY_PER_BLOCK;
  81         case META_SIT:
  82                 return SIT_BLK_CNT(sbi);
  83         case META_SSA:
  84         case META_CP:
  85                 return 0;
  86         default:
  87                 BUG();
  88         }
  89 }
  90
  91 /*
  92  * Readahead CP/NAT/SIT/SSA pages
  93  */
  94 int ra_meta_pages(struct f2fs_sb_info *sbi, int start, int nrpages, int type)
  95 {
  96         block_t prev_blk_addr = 0;
  97         struct page *page;
  98         int blkno = start;
  99         int max_blks = get_max_meta_blks(sbi, type);
 100
 101         struct f2fs_io_info fio = {
 102                 .type = META,
 103                 .rw = READ_SYNC | REQ_META | REQ_PRIO
 104         };
 105
 106         for (; nrpages-- > 0; blkno++) {
 107                 block_t blk_addr;
 108
 109                 switch (type) {
 110                 case META_NAT:
 111                         /* get nat block addr */
 112                         if (unlikely(blkno >= max_blks))
 113                                 blkno = 0;
 114                         blk_addr = current_nat_addr(sbi,
 115                                         blkno * NAT_ENTRY_PER_BLOCK);
 116                         break;
 117                 case META_SIT:
 118                         /* get sit block addr */
 119                         if (unlikely(blkno >= max_blks))
 120                                 goto out;
 121                         blk_addr = current_sit_addr(sbi,
 122                                         blkno * SIT_ENTRY_PER_BLOCK);
 123                         if (blkno != start && prev_blk_addr + 1 != blk_addr)
 124                                 goto out;
 125                         prev_blk_addr = blk_addr;
 126                         break;
 127                 case META_SSA:
 128                 case META_CP:
 129                         /* get ssa/cp block addr */
 130                         blk_addr = blkno;
 131                         break;
 132                 default:
 133                         BUG();
 134                 }
 135
 136                 page = grab_cache_page(META_MAPPING(sbi), blk_addr);
 137                 if (!page)
 138                         continue;
 139                 if (PageUptodate(page)) {
 140                         mark_page_accessed(page);
 141                         f2fs_put_page(page, 1);
 142                         continue;
 143                 }
 144
 145                 f2fs_submit_page_mbio(sbi, page, blk_addr, &fio);
 146                 mark_page_accessed(page);
 147                 f2fs_put_page(page, 0);
 148         }
 149 out:
 150         f2fs_submit_merged_bio(sbi, META, READ);
 151         return blkno - start;
 152 }
 153
 154 static int f2fs_write_meta_page(struct page *page,
 155                                 struct writeback_control *wbc)
 156 {
 157         struct inode *inode = page->mapping->host;
 158         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
 159
 160         if (unlikely(sbi->por_doing))
 161                 goto redirty_out;
 162         if (wbc->for_reclaim)
 163                 goto redirty_out;
 164
 165         /* Should not write any meta pages, if any IO error was occurred */
 166         if (unlikely(is_set_ckpt_flags(F2FS_CKPT(sbi), CP_ERROR_FLAG)))
 167                 goto no_write;
 168
 169         f2fs_wait_on_page_writeback(page, META);
 170         write_meta_page(sbi, page);
 171 no_write:
 172         dec_page_count(sbi, F2FS_DIRTY_META);
 173         unlock_page(page);
 174         return 0;
 175
 176 redirty_out:
 177         dec_page_count(sbi, F2FS_DIRTY_META);
 178         wbc->pages_skipped++;
 179         account_page_redirty(page);
 180         set_page_dirty(page);
 181         return AOP_WRITEPAGE_ACTIVATE;
 182 }
 183
 184 static int f2fs_write_meta_pages(struct address_space *mapping,
 185                                 struct writeback_control *wbc)
 186 {
 187         struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
 188         long diff, written;
 189
 190         /* collect a number of dirty meta pages and write together */
 191         if (wbc->for_kupdate ||
 192                 get_pages(sbi, F2FS_DIRTY_META) < nr_pages_to_skip(sbi, META))
 193                 goto skip_write;
 194
 195         /* if mounting is failed, skip writing node pages */
 196         mutex_lock(&sbi->cp_mutex);
 197         diff = nr_pages_to_write(sbi, META, wbc);
 198         written = sync_meta_pages(sbi, META, wbc->nr_to_write);
 199         mutex_unlock(&sbi->cp_mutex);
 200         wbc->nr_to_write = max((long)0, wbc->nr_to_write - written - diff);
 201         return 0;
 202
 203 skip_write:
 204         wbc->pages_skipped += get_pages(sbi, F2FS_DIRTY_META);
 205         return 0;
 206 }
 207
 208 long sync_meta_pages(struct f2fs_sb_info *sbi, enum page_type type,
 209                                                 long nr_to_write)
 210 {
 211         struct address_space *mapping = META_MAPPING(sbi);
 212         pgoff_t index = 0, end = LONG_MAX;
 213         struct pagevec pvec;
 214         long nwritten = 0;
 215         struct writeback_control wbc = {
 216                 .for_reclaim = 0,
 217         };
 218
 219         pagevec_init(&pvec, 0);
 220
 221         while (index <= end) {
 222                 int i, nr_pages;
 223                 nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
 224                                 PAGECACHE_TAG_DIRTY,
 225                                 min(end - index, (pgoff_t)PAGEVEC_SIZE-1) + 1);
 226                 if (unlikely(nr_pages == 0))
 227                         break;
 228
 229                 for (i = 0; i < nr_pages; i++) {
 230                         struct page *page = pvec.pages[i];
 231
 232                         lock_page(page);
 233
 234                         if (unlikely(page->mapping != mapping)) {
 235 continue_unlock:
 236                                 unlock_page(page);
 237                                 continue;
 238                         }
 239                         if (!PageDirty(page)) {
 240                                 /* someone wrote it for us */
 241                                 goto continue_unlock;
 242                         }
 243
 244                         if (!clear_page_dirty_for_io(page))
 245                                 goto continue_unlock;
 246
 247                         if (f2fs_write_meta_page(page, &wbc)) {
 248                                 unlock_page(page);
 249                                 break;
 250                         }
 251                         nwritten++;
 252                         if (unlikely(nwritten >= nr_to_write))
 253                                 break;
 254                 }
 255                 pagevec_release(&pvec);
 256                 cond_resched();
 257         }
 258
 259         if (nwritten)
 260                 f2fs_submit_merged_bio(sbi, type, WRITE);
 261
 262         return nwritten;
 263 }
 264
 265 static int f2fs_set_meta_page_dirty(struct page *page)
 266 {
 267         struct address_space *mapping = page->mapping;
 268         struct f2fs_sb_info *sbi = F2FS_SB(mapping->host->i_sb);
 269
 270         trace_f2fs_set_page_dirty(page, META);
 271
 272         SetPageUptodate(page);
 273         if (!PageDirty(page)) {
 274                 __set_page_dirty_nobuffers(page);
 275                 inc_page_count(sbi, F2FS_DIRTY_META);
 276                 return 1;
 277         }
 278         return 0;
 279 }
 280
 281 const struct address_space_operations f2fs_meta_aops = {
 282         .writepage      = f2fs_write_meta_page,
 283         .writepages     = f2fs_write_meta_pages,
 284         .set_page_dirty = f2fs_set_meta_page_dirty,
 285 };
 286
 287 int acquire_orphan_inode(struct f2fs_sb_info *sbi)
 288 {
 289         int err = 0;
 290
 291         spin_lock(&sbi->orphan_inode_lock);
 292         if (unlikely(sbi->n_orphans >= sbi->max_orphans))
 293                 err = -ENOSPC;
 294         else
 295                 sbi->n_orphans++;
 296         spin_unlock(&sbi->orphan_inode_lock);
 297
 298         return err;
 299 }
 300
 301 void release_orphan_inode(struct f2fs_sb_info *sbi)
 302 {
 303         spin_lock(&sbi->orphan_inode_lock);
 304         f2fs_bug_on(sbi->n_orphans == 0);
 305         sbi->n_orphans--;
 306         spin_unlock(&sbi->orphan_inode_lock);
 307 }
 308
 309 void add_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
 310 {
 311         struct list_head *head;
 312         struct orphan_inode_entry *new, *orphan;
 313
 314         new = f2fs_kmem_cache_alloc(orphan_entry_slab, GFP_ATOMIC);
 315         new->ino = ino;
 316
 317         spin_lock(&sbi->orphan_inode_lock);
 318         head = &sbi->orphan_inode_list;
 319         list_for_each_entry(orphan, head, list) {
 320                 if (orphan->ino == ino) {
 321                         spin_unlock(&sbi->orphan_inode_lock);
 322                         kmem_cache_free(orphan_entry_slab, new);
 323                         return;
 324                 }
 325
 326                 if (orphan->ino > ino)
 327                         break;
 328         }
 329
 330         /* add new orphan entry into list which is sorted by inode number */
 331         list_add_tail(&new->list, &orphan->list);
 332         spin_unlock(&sbi->orphan_inode_lock);
 333 }
 334
 335 void remove_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
 336 {
 337         struct list_head *head;
 338         struct orphan_inode_entry *orphan;
 339
 340         spin_lock(&sbi->orphan_inode_lock);
 341         head = &sbi->orphan_inode_list;
 342         list_for_each_entry(orphan, head, list) {
 343                 if (orphan->ino == ino) {
 344                         list_del(&orphan->list);
 345                         f2fs_bug_on(sbi->n_orphans == 0);
 346                         sbi->n_orphans--;
 347                         spin_unlock(&sbi->orphan_inode_lock);
 348                         kmem_cache_free(orphan_entry_slab, orphan);
 349                         return;
 350                 }
 351         }
 352         spin_unlock(&sbi->orphan_inode_lock);
 353 }
 354
 355 static void recover_orphan_inode(struct f2fs_sb_info *sbi, nid_t ino)
 356 {
 357         struct inode *inode = f2fs_iget(sbi->sb, ino);
 358         f2fs_bug_on(IS_ERR(inode));
 359         clear_nlink(inode);
 360
 361         /* truncate all the data during iput */
 362         iput(inode);
 363 }
 364
 365 void recover_orphan_inodes(struct f2fs_sb_info *sbi)
 366 {
 367         block_t start_blk, orphan_blkaddr, i, j;
 368
 369         if (!is_set_ckpt_flags(F2FS_CKPT(sbi), CP_ORPHAN_PRESENT_FLAG))
 370                 return;
 371
 372         sbi->por_doing = true;
 373         start_blk = __start_cp_addr(sbi) + 1;
 374         orphan_blkaddr = __start_sum_addr(sbi) - 1;
 375
 376         ra_meta_pages(sbi, start_blk, orphan_blkaddr, META_CP);
 377
 378         for (i = 0; i < orphan_blkaddr; i++) {
 379                 struct page *page = get_meta_page(sbi, start_blk + i);
 380                 struct f2fs_orphan_block *orphan_blk;
 381
 382                 orphan_blk = (struct f2fs_orphan_block *)page_address(page);
 383                 for (j = 0; j < le32_to_cpu(orphan_blk->entry_count); j++) {
 384                         nid_t ino = le32_to_cpu(orphan_blk->ino[j]);
 385                         recover_orphan_inode(sbi, ino);
 386                 }
 387                 f2fs_put_page(page, 1);
 388         }
 389         /* clear Orphan Flag */
 390         clear_ckpt_flags(F2FS_CKPT(sbi), CP_ORPHAN_PRESENT_FLAG);
 391         sbi->por_doing = false;
 392         return;
 393 }
 394
 395 static void write_orphan_inodes(struct f2fs_sb_info *sbi, block_t start_blk)
 396 {
 397         struct list_head *head;
 398         struct f2fs_orphan_block *orphan_blk = NULL;
 399         unsigned int nentries = 0;
 400         unsigned short index;
 401         unsigned short orphan_blocks = (unsigned short)((sbi->n_orphans +
 402                 (F2FS_ORPHANS_PER_BLOCK - 1)) / F2FS_ORPHANS_PER_BLOCK);
 403         struct page *page = NULL;
 404         struct orphan_inode_entry *orphan = NULL;
 405
 406         for (index = 0; index < orphan_blocks; index++)
 407                 grab_meta_page(sbi, start_blk + index);
 408
 409         index = 1;
 410         spin_lock(&sbi->orphan_inode_lock);
 411         head = &sbi->orphan_inode_list;
 412
 413         /* loop for each orphan inode entry and write them in Jornal block */
 414         list_for_each_entry(orphan, head, list) {
 415                 if (!page) {
 416                         page = find_get_page(META_MAPPING(sbi), start_blk++);
 417                         f2fs_bug_on(!page);
 418                         orphan_blk =
 419                                 (struct f2fs_orphan_block *)page_address(page);
 420                         memset(orphan_blk, 0, sizeof(*orphan_blk));
 421                         f2fs_put_page(page, 0);
 422                 }
 423
 424                 orphan_blk->ino[nentries++] = cpu_to_le32(orphan->ino);
 425
 426                 if (nentries == F2FS_ORPHANS_PER_BLOCK) {
 427                         /*
 428                          * an orphan block is full of 1020 entries,
 429                          * then we need to flush current orphan blocks
 430                          * and bring another one in memory
 431                          */
 432                         orphan_blk->blk_addr = cpu_to_le16(index);
 433                         orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
 434                         orphan_blk->entry_count = cpu_to_le32(nentries);
 435                         set_page_dirty(page);
 436                         f2fs_put_page(page, 1);
 437                         index++;
 438                         nentries = 0;
 439                         page = NULL;
 440                 }
 441         }
 442
 443         if (page) {
 444                 orphan_blk->blk_addr = cpu_to_le16(index);
 445                 orphan_blk->blk_count = cpu_to_le16(orphan_blocks);
 446                 orphan_blk->entry_count = cpu_to_le32(nentries);
 447                 set_page_dirty(page);
 448                 f2fs_put_page(page, 1);
 449         }
 450
 451         spin_unlock(&sbi->orphan_inode_lock);
 452 }
 453
 454 static struct page *validate_checkpoint(struct f2fs_sb_info *sbi,
 455                                 block_t cp_addr, unsigned long long *version)
 456 {
 457         struct page *cp_page_1, *cp_page_2 = NULL;
 458         unsigned long blk_size = sbi->blocksize;
 459         struct f2fs_checkpoint *cp_block;
 460         unsigned long long cur_version = 0, pre_version = 0;
 461         size_t crc_offset;
 462         __u32 crc = 0;
 463
 464         /* Read the 1st cp block in this CP pack */
 465         cp_page_1 = get_meta_page(sbi, cp_addr);
 466
 467         /* get the version number */
 468         cp_block = (struct f2fs_checkpoint *)page_address(cp_page_1);
 469         crc_offset = le32_to_cpu(cp_block->checksum_offset);
 470         if (crc_offset >= blk_size)
 471                 goto invalid_cp1;
 472
 473         crc = le32_to_cpu(*((__u32 *)((unsigned char *)cp_block + crc_offset)));
 474         if (!f2fs_crc_valid(crc, cp_block, crc_offset))
 475                 goto invalid_cp1;
 476
 477         pre_version = cur_cp_version(cp_block);
 478
 479         /* Read the 2nd cp block in this CP pack */
 480         cp_addr += le32_to_cpu(cp_block->cp_pack_total_block_count) - 1;
 481         cp_page_2 = get_meta_page(sbi, cp_addr);
 482
 483         cp_block = (struct f2fs_checkpoint *)page_address(cp_page_2);
 484         crc_offset = le32_to_cpu(cp_block->checksum_offset);
 485         if (crc_offset >= blk_size)
 486                 goto invalid_cp2;
 487
 488         crc = le32_to_cpu(*((__u32 *)((unsigned char *)cp_block + crc_offset)));
 489         if (!f2fs_crc_valid(crc, cp_block, crc_offset))
 490                 goto invalid_cp2;
 491
 492         cur_version = cur_cp_version(cp_block);
 493
 494         if (cur_version == pre_version) {
 495                 *version = cur_version;
 496                 f2fs_put_page(cp_page_2, 1);
 497                 return cp_page_1;
 498         }
 499 invalid_cp2:
 500         f2fs_put_page(cp_page_2, 1);
 501 invalid_cp1:
 502         f2fs_put_page(cp_page_1, 1);
 503         return NULL;
 504 }
 505
 506 int get_valid_checkpoint(struct f2fs_sb_info *sbi)
 507 {
 508         struct f2fs_checkpoint *cp_block;
 509         struct f2fs_super_block *fsb = sbi->raw_super;
 510         struct page *cp1, *cp2, *cur_page;
 511         unsigned long blk_size = sbi->blocksize;
 512         unsigned long long cp1_version = 0, cp2_version = 0;
 513         unsigned long long cp_start_blk_no;
 514
 515         sbi->ckpt = kzalloc(blk_size, GFP_KERNEL);
 516         if (!sbi->ckpt)
 517                 return -ENOMEM;
 518         /*
 519          * Finding out valid cp block involves read both
 520          * sets( cp pack1 and cp pack 2)
 521          */
 522         cp_start_blk_no = le32_to_cpu(fsb->cp_blkaddr);
 523         cp1 = validate_checkpoint(sbi, cp_start_blk_no, &cp1_version);
 524
 525         /* The second checkpoint pack should start at the next segment */
 526         cp_start_blk_no += ((unsigned long long)1) <<
 527                                 le32_to_cpu(fsb->log_blocks_per_seg);
 528         cp2 = validate_checkpoint(sbi, cp_start_blk_no, &cp2_version);
 529
 530         if (cp1 && cp2) {
 531                 if (ver_after(cp2_version, cp1_version))
 532                         cur_page = cp2;
 533                 else
 534                         cur_page = cp1;
 535         } else if (cp1) {
 536                 cur_page = cp1;
 537         } else if (cp2) {
 538                 cur_page = cp2;
 539         } else {
 540                 goto fail_no_cp;
 541         }
 542
 543         cp_block = (struct f2fs_checkpoint *)page_address(cur_page);
 544         memcpy(sbi->ckpt, cp_block, blk_size);
 545
 546         f2fs_put_page(cp1, 1);
 547         f2fs_put_page(cp2, 1);
 548         return 0;
 549
 550 fail_no_cp:
 551         kfree(sbi->ckpt);
 552         return -EINVAL;
 553 }
 554
 555 static int __add_dirty_inode(struct inode *inode, struct dir_inode_entry *new)
 556 {
 557         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
 558         struct list_head *head = &sbi->dir_inode_list;
 559         struct dir_inode_entry *entry;
 560
 561         list_for_each_entry(entry, head, list)
 562                 if (unlikely(entry->inode == inode))
 563                         return -EEXIST;
 564
 565         list_add_tail(&new->list, head);
 566         stat_inc_dirty_dir(sbi);
 567         return 0;
 568 }
 569
 570 void set_dirty_dir_page(struct inode *inode, struct page *page)
 571 {
 572         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
 573         struct dir_inode_entry *new;
 574         int ret = 0;
 575
 576         if (!S_ISDIR(inode->i_mode))
 577                 return;
 578
 579         new = f2fs_kmem_cache_alloc(inode_entry_slab, GFP_NOFS);
 580         new->inode = inode;
 581         INIT_LIST_HEAD(&new->list);
 582
 583         spin_lock(&sbi->dir_inode_lock);
 584         ret = __add_dirty_inode(inode, new);
 585         inode_inc_dirty_dents(inode);
 586         SetPagePrivate(page);
 587         spin_unlock(&sbi->dir_inode_lock);
 588
 589         if (ret)
 590                 kmem_cache_free(inode_entry_slab, new);
 591 }
 592
 593 void add_dirty_dir_inode(struct inode *inode)
 594 {
 595         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
 596         struct dir_inode_entry *new =
 597                         f2fs_kmem_cache_alloc(inode_entry_slab, GFP_NOFS);
 598         int ret = 0;
 599
 600         new->inode = inode;
 601         INIT_LIST_HEAD(&new->list);
 602
 603         spin_lock(&sbi->dir_inode_lock);
 604         ret = __add_dirty_inode(inode, new);
 605         spin_unlock(&sbi->dir_inode_lock);
 606
 607         if (ret)
 608                 kmem_cache_free(inode_entry_slab, new);
 609 }
 610
 611 void remove_dirty_dir_inode(struct inode *inode)
 612 {
 613         struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
 614         struct list_head *head;
 615         struct dir_inode_entry *entry;
 616
 617         if (!S_ISDIR(inode->i_mode))
 618                 return;
 619
 620         spin_lock(&sbi->dir_inode_lock);
 621         if (get_dirty_dents(inode)) {
 622                 spin_unlock(&sbi->dir_inode_lock);
 623                 return;
 624         }
 625
 626         head = &sbi->dir_inode_list;
 627         list_for_each_entry(entry, head, list) {
 628                 if (entry->inode == inode) {
 629                         list_del(&entry->list);
 630                         stat_dec_dirty_dir(sbi);
 631                         spin_unlock(&sbi->dir_inode_lock);
 632                         kmem_cache_free(inode_entry_slab, entry);
 633                         goto done;
 634                 }
 635         }
 636         spin_unlock(&sbi->dir_inode_lock);
 637
 638 done:
 639         /* Only from the recovery routine */
 640         if (is_inode_flag_set(F2FS_I(inode), FI_DELAY_IPUT)) {
 641                 clear_inode_flag(F2FS_I(inode), FI_DELAY_IPUT);
 642                 iput(inode);
 643         }
 644 }
 645
 646 struct inode *check_dirty_dir_inode(struct f2fs_sb_info *sbi, nid_t ino)
 647 {
 648
 649         struct list_head *head;
 650         struct inode *inode = NULL;
 651         struct dir_inode_entry *entry;
 652
 653         spin_lock(&sbi->dir_inode_lock);
 654
 655         head = &sbi->dir_inode_list;
 656         list_for_each_entry(entry, head, list) {
 657                 if (entry->inode->i_ino == ino) {
 658                         inode = entry->inode;
 659                         break;
 660                 }
 661         }
 662         spin_unlock(&sbi->dir_inode_lock);
 663         return inode;
 664 }
 665
 666 void sync_dirty_dir_inodes(struct f2fs_sb_info *sbi)
 667 {
 668         struct list_head *head;
 669         struct dir_inode_entry *entry;
 670         struct inode *inode;
 671 retry:
 672         spin_lock(&sbi->dir_inode_lock);
 673
 674         head = &sbi->dir_inode_list;
 675         if (list_empty(head)) {
 676                 spin_unlock(&sbi->dir_inode_lock);
 677                 return;
 678         }
 679         entry = list_entry(head->next, struct dir_inode_entry, list);
 680         inode = igrab(entry->inode);
 681         spin_unlock(&sbi->dir_inode_lock);
 682         if (inode) {
 683                 filemap_fdatawrite(inode->i_mapping);
 684                 iput(inode);
 685         } else {
 686                 /*
 687                  * We should submit bio, since it exists several
 688                  * wribacking dentry pages in the freeing inode.
 689                  */
 690                 f2fs_submit_merged_bio(sbi, DATA, WRITE);
 691         }
 692         goto retry;
 693 }
 694
 695 /*
 696  * Freeze all the FS-operations for checkpoint.
 697  */
 698 static void block_operations(struct f2fs_sb_info *sbi)
 699 {
 700         struct writeback_control wbc = {
 701                 .sync_mode = WB_SYNC_ALL,
 702                 .nr_to_write = LONG_MAX,
 703                 .for_reclaim = 0,
 704         };
 705         struct blk_plug plug;
 706
 707         blk_start_plug(&plug);
 708
 709 retry_flush_dents:
 710         f2fs_lock_all(sbi);
 711         /* write all the dirty dentry pages */
 712         if (get_pages(sbi, F2FS_DIRTY_DENTS)) {
 713                 f2fs_unlock_all(sbi);
 714                 sync_dirty_dir_inodes(sbi);
 715                 goto retry_flush_dents;
 716         }
 717
 718         /*
 719          * POR: we should ensure that there is no dirty node pages
 720          * until finishing nat/sit flush.
 721          */
 722 retry_flush_nodes:
 723         mutex_lock(&sbi->node_write);
 724
 725         if (get_pages(sbi, F2FS_DIRTY_NODES)) {
 726                 mutex_unlock(&sbi->node_write);
 727                 sync_node_pages(sbi, 0, &wbc);
 728                 goto retry_flush_nodes;
 729         }
 730         blk_finish_plug(&plug);
 731 }
 732
 733 static void unblock_operations(struct f2fs_sb_info *sbi)
 734 {
 735         mutex_unlock(&sbi->node_write);
 736         f2fs_unlock_all(sbi);
 737 }
 738
 739 static void wait_on_all_pages_writeback(struct f2fs_sb_info *sbi)
 740 {
 741         DEFINE_WAIT(wait);
 742
 743         for (;;) {
 744                 prepare_to_wait(&sbi->cp_wait, &wait, TASK_UNINTERRUPTIBLE);
 745
 746                 if (!get_pages(sbi, F2FS_WRITEBACK))
 747                         break;
 748
 749                 io_schedule();
 750         }
 751         finish_wait(&sbi->cp_wait, &wait);
 752 }
 753
 754 static void do_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
 755 {
 756         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
 757         nid_t last_nid = 0;
 758         block_t start_blk;
 759         struct page *cp_page;
 760         unsigned int data_sum_blocks, orphan_blocks;
 761         __u32 crc32 = 0;
 762         void *kaddr;
 763         int i;
 764
 765         /* Flush all the NAT/SIT pages */
 766         while (get_pages(sbi, F2FS_DIRTY_META))
 767                 sync_meta_pages(sbi, META, LONG_MAX);
 768
 769         next_free_nid(sbi, &last_nid);
 770
 771         /*
 772          * modify checkpoint
 773          * version number is already updated
 774          */
 775         ckpt->elapsed_time = cpu_to_le64(get_mtime(sbi));
 776         ckpt->valid_block_count = cpu_to_le64(valid_user_blocks(sbi));
 777         ckpt->free_segment_count = cpu_to_le32(free_segments(sbi));
 778         for (i = 0; i < 3; i++) {
 779                 ckpt->cur_node_segno[i] =
 780                         cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_NODE));
 781                 ckpt->cur_node_blkoff[i] =
 782                         cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_NODE));
 783                 ckpt->alloc_type[i + CURSEG_HOT_NODE] =
 784                                 curseg_alloc_type(sbi, i + CURSEG_HOT_NODE);
 785         }
 786         for (i = 0; i < 3; i++) {
 787                 ckpt->cur_data_segno[i] =
 788                         cpu_to_le32(curseg_segno(sbi, i + CURSEG_HOT_DATA));
 789                 ckpt->cur_data_blkoff[i] =
 790                         cpu_to_le16(curseg_blkoff(sbi, i + CURSEG_HOT_DATA));
 791                 ckpt->alloc_type[i + CURSEG_HOT_DATA] =
 792                                 curseg_alloc_type(sbi, i + CURSEG_HOT_DATA);
 793         }
 794
 795         ckpt->valid_node_count = cpu_to_le32(valid_node_count(sbi));
 796         ckpt->valid_inode_count = cpu_to_le32(valid_inode_count(sbi));
 797         ckpt->next_free_nid = cpu_to_le32(last_nid);
 798
 799         /* 2 cp  + n data seg summary + orphan inode blocks */
 800         data_sum_blocks = npages_for_summary_flush(sbi);
 801         if (data_sum_blocks < 3)
 802                 set_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
 803         else
 804                 clear_ckpt_flags(ckpt, CP_COMPACT_SUM_FLAG);
 805
 806         orphan_blocks = (sbi->n_orphans + F2FS_ORPHANS_PER_BLOCK - 1)
 807                                         / F2FS_ORPHANS_PER_BLOCK;
 808         ckpt->cp_pack_start_sum = cpu_to_le32(1 + orphan_blocks);
 809
 810         if (is_umount) {
 811                 set_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
 812                 ckpt->cp_pack_total_block_count = cpu_to_le32(2 +
 813                         data_sum_blocks + orphan_blocks + NR_CURSEG_NODE_TYPE);
 814         } else {
 815                 clear_ckpt_flags(ckpt, CP_UMOUNT_FLAG);
 816                 ckpt->cp_pack_total_block_count = cpu_to_le32(2 +
 817                         data_sum_blocks + orphan_blocks);
 818         }
 819
 820         if (sbi->n_orphans)
 821                 set_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
 822         else
 823                 clear_ckpt_flags(ckpt, CP_ORPHAN_PRESENT_FLAG);
 824
 825         /* update SIT/NAT bitmap */
 826         get_sit_bitmap(sbi, __bitmap_ptr(sbi, SIT_BITMAP));
 827         get_nat_bitmap(sbi, __bitmap_ptr(sbi, NAT_BITMAP));
 828
 829         crc32 = f2fs_crc32(ckpt, le32_to_cpu(ckpt->checksum_offset));
 830         *((__le32 *)((unsigned char *)ckpt +
 831                                 le32_to_cpu(ckpt->checksum_offset)))
 832                                 = cpu_to_le32(crc32);
 833
 834         start_blk = __start_cp_addr(sbi);
 835
 836         /* write out checkpoint buffer at block 0 */
 837         cp_page = grab_meta_page(sbi, start_blk++);
 838         kaddr = page_address(cp_page);
 839         memcpy(kaddr, ckpt, (1 << sbi->log_blocksize));
 840         set_page_dirty(cp_page);
 841         f2fs_put_page(cp_page, 1);
 842
 843         if (sbi->n_orphans) {
 844                 write_orphan_inodes(sbi, start_blk);
 845                 start_blk += orphan_blocks;
 846         }
 847
 848         write_data_summaries(sbi, start_blk);
 849         start_blk += data_sum_blocks;
 850         if (is_umount) {
 851                 write_node_summaries(sbi, start_blk);
 852                 start_blk += NR_CURSEG_NODE_TYPE;
 853         }
 854
 855         /* writeout checkpoint block */
 856         cp_page = grab_meta_page(sbi, start_blk);
 857         kaddr = page_address(cp_page);
 858         memcpy(kaddr, ckpt, (1 << sbi->log_blocksize));
 859         set_page_dirty(cp_page);
 860         f2fs_put_page(cp_page, 1);
 861
 862         /* wait for previous submitted node/meta pages writeback */
 863         wait_on_all_pages_writeback(sbi);
 864
 865         filemap_fdatawait_range(NODE_MAPPING(sbi), 0, LONG_MAX);
 866         filemap_fdatawait_range(META_MAPPING(sbi), 0, LONG_MAX);
 867
 868         /* update user_block_counts */
 869         sbi->last_valid_block_count = sbi->total_valid_block_count;
 870         sbi->alloc_valid_block_count = 0;
 871
 872         /* Here, we only have one bio having CP pack */
 873         sync_meta_pages(sbi, META_FLUSH, LONG_MAX);
 874
 875         if (unlikely(!is_set_ckpt_flags(ckpt, CP_ERROR_FLAG))) {
 876                 clear_prefree_segments(sbi);
 877                 F2FS_RESET_SB_DIRT(sbi);
 878         }
 879 }
 880
 881 /*
 882  * We guarantee that this checkpoint procedure should not fail.
 883  */
 884 void write_checkpoint(struct f2fs_sb_info *sbi, bool is_umount)
 885 {
 886         struct f2fs_checkpoint *ckpt = F2FS_CKPT(sbi);
 887         unsigned long long ckpt_ver;
 888
 889         trace_f2fs_write_checkpoint(sbi->sb, is_umount, "start block_ops");
 890
 891         mutex_lock(&sbi->cp_mutex);
 892         block_operations(sbi);
 893
 894         trace_f2fs_write_checkpoint(sbi->sb, is_umount, "finish block_ops");
 895
 896         f2fs_submit_merged_bio(sbi, DATA, WRITE);
 897         f2fs_submit_merged_bio(sbi, NODE, WRITE);
 898         f2fs_submit_merged_bio(sbi, META, WRITE);
 899
 900         /*
 901          * update checkpoint pack index
 902          * Increase the version number so that
 903          * SIT entries and seg summaries are written at correct place
 904          */
 905         ckpt_ver = cur_cp_version(ckpt);
 906         ckpt->checkpoint_ver = cpu_to_le64(++ckpt_ver);
 907
 908         /* write cached NAT/SIT entries to NAT/SIT area */
 909         flush_nat_entries(sbi);
 910         flush_sit_entries(sbi);
 911
 912         /* unlock all the fs_lock[] in do_checkpoint() */
 913         do_checkpoint(sbi, is_umount);
 914
 915         unblock_operations(sbi);
 916         mutex_unlock(&sbi->cp_mutex);
 917
 918         stat_inc_cp_count(sbi->stat_info);
 919         trace_f2fs_write_checkpoint(sbi->sb, is_umount, "finish checkpoint");
 920 }
 921
 922 void init_orphan_info(struct f2fs_sb_info *sbi)
 923 {
 924         spin_lock_init(&sbi->orphan_inode_lock);
 925         INIT_LIST_HEAD(&sbi->orphan_inode_list);
 926         sbi->n_orphans = 0;
 927         /*
 928          * considering 512 blocks in a segment 8 blocks are needed for cp
 929          * and log segment summaries. Remaining blocks are used to keep
 930          * orphan entries with the limitation one reserved segment
 931          * for cp pack we can have max 1020*504 orphan entries
 932          */
 933         sbi->max_orphans = (sbi->blocks_per_seg - 2 - NR_CURSEG_TYPE)
 934                                 * F2FS_ORPHANS_PER_BLOCK;
 935 }
 936
 937 int __init create_checkpoint_caches(void)
 938 {
 939         orphan_entry_slab = f2fs_kmem_cache_create("f2fs_orphan_entry",
 940                         sizeof(struct orphan_inode_entry));
 941         if (!orphan_entry_slab)
 942                 return -ENOMEM;
 943         inode_entry_slab = f2fs_kmem_cache_create("f2fs_dirty_dir_entry",
 944                         sizeof(struct dir_inode_entry));
 945         if (!inode_entry_slab) {
 946                 kmem_cache_destroy(orphan_entry_slab);
 947                 return -ENOMEM;
 948         }
 949         return 0;
 950 }
 951
 952 void destroy_checkpoint_caches(void)
 953 {
 954         kmem_cache_destroy(orphan_entry_slab);
 955         kmem_cache_destroy(inode_entry_slab);
 956 }