fs/f2fs/data.c

   1 /*
   2  * fs/f2fs/data.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/buffer_head.h>
  14 #include <linux/mpage.h>
  15 #include <linux/writeback.h>
  16 #include <linux/backing-dev.h>
  17 #include <linux/pagevec.h>
  18 #include <linux/blkdev.h>
  19 #include <linux/bio.h>
  20 #include <linux/prefetch.h>
  21 #include <linux/uio.h>
  22 #include <linux/cleancache.h>
  23
  24 #include "f2fs.h"
  25 #include "node.h"
  26 #include "segment.h"
  27 #include "trace.h"
  28 #include <trace/events/f2fs.h>
  29 #include <trace/events/android_fs.h>
  30
  31 static void f2fs_read_end_io(struct bio *bio)
  32 {
  33         struct bio_vec *bvec;
  34         int i;
  35
  36         if (f2fs_bio_encrypted(bio)) {
  37                 if (bio->bi_error) {
  38                         f2fs_release_crypto_ctx(bio->bi_private);
  39                 } else {
  40                         f2fs_end_io_crypto_work(bio->bi_private, bio);
  41                         return;
  42                 }
  43         }
  44
  45         bio_for_each_segment_all(bvec, bio, i) {
  46                 struct page *page = bvec->bv_page;
  47
  48                 if (!bio->bi_error) {
  49                         SetPageUptodate(page);
  50                 } else {
  51                         ClearPageUptodate(page);
  52                         SetPageError(page);
  53                 }
  54                 unlock_page(page);
  55         }
  56         bio_put(bio);
  57 }
  58
  59 static void f2fs_write_end_io(struct bio *bio)
  60 {
  61         struct f2fs_sb_info *sbi = bio->bi_private;
  62         struct bio_vec *bvec;
  63         int i;
  64
  65         bio_for_each_segment_all(bvec, bio, i) {
  66                 struct page *page = bvec->bv_page;
  67
  68                 f2fs_restore_and_release_control_page(&page);
  69
  70                 if (unlikely(bio->bi_error)) {
  71                         set_page_dirty(page);
  72                         set_bit(AS_EIO, &page->mapping->flags);
  73                         f2fs_stop_checkpoint(sbi);
  74                 }
  75                 end_page_writeback(page);
  76                 dec_page_count(sbi, F2FS_WRITEBACK);
  77         }
  78
  79         if (!get_pages(sbi, F2FS_WRITEBACK) &&
  80                         !list_empty(&sbi->cp_wait.task_list))
  81                 wake_up(&sbi->cp_wait);
  82
  83         bio_put(bio);
  84 }
  85
  86 /*
  87  * Low-level block read/write IO operations.
  88  */
  89 static struct bio *__bio_alloc(struct f2fs_sb_info *sbi, block_t blk_addr,
  90                                 int npages, bool is_read)
  91 {
  92         struct bio *bio;
  93
  94         bio = f2fs_bio_alloc(npages);
  95
  96         bio->bi_bdev = sbi->sb->s_bdev;
  97         bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(blk_addr);
  98         bio->bi_end_io = is_read ? f2fs_read_end_io : f2fs_write_end_io;
  99         bio->bi_private = is_read ? NULL : sbi;
 100
 101         return bio;
 102 }
 103
 104 static void __submit_merged_bio(struct f2fs_bio_info *io)
 105 {
 106         struct f2fs_io_info *fio = &io->fio;
 107
 108         if (!io->bio)
 109                 return;
 110
 111         if (is_read_io(fio->rw))
 112                 trace_f2fs_submit_read_bio(io->sbi->sb, fio, io->bio);
 113         else
 114                 trace_f2fs_submit_write_bio(io->sbi->sb, fio, io->bio);
 115
 116         submit_bio(fio->rw, io->bio);
 117         io->bio = NULL;
 118 }
 119
 120 void f2fs_submit_merged_bio(struct f2fs_sb_info *sbi,
 121                                 enum page_type type, int rw)
 122 {
 123         enum page_type btype = PAGE_TYPE_OF_BIO(type);
 124         struct f2fs_bio_info *io;
 125
 126         io = is_read_io(rw) ? &sbi->read_io : &sbi->write_io[btype];
 127
 128         down_write(&io->io_rwsem);
 129
 130         /* change META to META_FLUSH in the checkpoint procedure */
 131         if (type >= META_FLUSH) {
 132                 io->fio.type = META_FLUSH;
 133                 if (test_opt(sbi, NOBARRIER))
 134                         io->fio.rw = WRITE_FLUSH | REQ_META | REQ_PRIO;
 135                 else
 136                         io->fio.rw = WRITE_FLUSH_FUA | REQ_META | REQ_PRIO;
 137         }
 138         __submit_merged_bio(io);
 139         up_write(&io->io_rwsem);
 140 }
 141
 142 /*
 143  * Fill the locked page with data located in the block address.
 144  * Return unlocked page.
 145  */
 146 int f2fs_submit_page_bio(struct f2fs_io_info *fio)
 147 {
 148         struct bio *bio;
 149         struct page *page = fio->encrypted_page ? fio->encrypted_page : fio->page;
 150
 151         trace_f2fs_submit_page_bio(page, fio);
 152         f2fs_trace_ios(fio, 0);
 153
 154         /* Allocate a new bio */
 155         bio = __bio_alloc(fio->sbi, fio->blk_addr, 1, is_read_io(fio->rw));
 156
 157         if (bio_add_page(bio, page, PAGE_CACHE_SIZE, 0) < PAGE_CACHE_SIZE) {
 158                 bio_put(bio);
 159                 return -EFAULT;
 160         }
 161
 162         submit_bio(fio->rw, bio);
 163         return 0;
 164 }
 165
 166 void f2fs_submit_page_mbio(struct f2fs_io_info *fio)
 167 {
 168         struct f2fs_sb_info *sbi = fio->sbi;
 169         enum page_type btype = PAGE_TYPE_OF_BIO(fio->type);
 170         struct f2fs_bio_info *io;
 171         bool is_read = is_read_io(fio->rw);
 172         struct page *bio_page;
 173
 174         io = is_read ? &sbi->read_io : &sbi->write_io[btype];
 175
 176         verify_block_addr(sbi, fio->blk_addr);
 177
 178         down_write(&io->io_rwsem);
 179
 180         if (!is_read)
 181                 inc_page_count(sbi, F2FS_WRITEBACK);
 182
 183         if (io->bio && (io->last_block_in_bio != fio->blk_addr - 1 ||
 184                                                 io->fio.rw != fio->rw))
 185                 __submit_merged_bio(io);
 186 alloc_new:
 187         if (io->bio == NULL) {
 188                 int bio_blocks = MAX_BIO_BLOCKS(sbi);
 189
 190                 io->bio = __bio_alloc(sbi, fio->blk_addr, bio_blocks, is_read);
 191                 io->fio = *fio;
 192         }
 193
 194         bio_page = fio->encrypted_page ? fio->encrypted_page : fio->page;
 195
 196         if (bio_add_page(io->bio, bio_page, PAGE_CACHE_SIZE, 0) <
 197                                                         PAGE_CACHE_SIZE) {
 198                 __submit_merged_bio(io);
 199                 goto alloc_new;
 200         }
 201
 202         io->last_block_in_bio = fio->blk_addr;
 203         f2fs_trace_ios(fio, 0);
 204
 205         up_write(&io->io_rwsem);
 206         trace_f2fs_submit_page_mbio(fio->page, fio);
 207 }
 208
 209 /*
 210  * Lock ordering for the change of data block address:
 211  * ->data_page
 212  *  ->node_page
 213  *    update block addresses in the node page
 214  */
 215 void set_data_blkaddr(struct dnode_of_data *dn)
 216 {
 217         struct f2fs_node *rn;
 218         __le32 *addr_array;
 219         struct page *node_page = dn->node_page;
 220         unsigned int ofs_in_node = dn->ofs_in_node;
 221
 222         f2fs_wait_on_page_writeback(node_page, NODE);
 223
 224         rn = F2FS_NODE(node_page);
 225
 226         /* Get physical address of data block */
 227         addr_array = blkaddr_in_node(rn);
 228         addr_array[ofs_in_node] = cpu_to_le32(dn->data_blkaddr);
 229         set_page_dirty(node_page);
 230 }
 231
 232 int reserve_new_block(struct dnode_of_data *dn)
 233 {
 234         struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
 235
 236         if (unlikely(is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC)))
 237                 return -EPERM;
 238         if (unlikely(!inc_valid_block_count(sbi, dn->inode, 1)))
 239                 return -ENOSPC;
 240
 241         trace_f2fs_reserve_new_block(dn->inode, dn->nid, dn->ofs_in_node);
 242
 243         dn->data_blkaddr = NEW_ADDR;
 244         set_data_blkaddr(dn);
 245         mark_inode_dirty(dn->inode);
 246         sync_inode_page(dn);
 247         return 0;
 248 }
 249
 250 int f2fs_reserve_block(struct dnode_of_data *dn, pgoff_t index)
 251 {
 252         bool need_put = dn->inode_page ? false : true;
 253         int err;
 254
 255         err = get_dnode_of_data(dn, index, ALLOC_NODE);
 256         if (err)
 257                 return err;
 258
 259         if (dn->data_blkaddr == NULL_ADDR)
 260                 err = reserve_new_block(dn);
 261         if (err || need_put)
 262                 f2fs_put_dnode(dn);
 263         return err;
 264 }
 265
 266 int f2fs_get_block(struct dnode_of_data *dn, pgoff_t index)
 267 {
 268         struct extent_info ei;
 269         struct inode *inode = dn->inode;
 270
 271         if (f2fs_lookup_extent_cache(inode, index, &ei)) {
 272                 dn->data_blkaddr = ei.blk + index - ei.fofs;
 273                 return 0;
 274         }
 275
 276         return f2fs_reserve_block(dn, index);
 277 }
 278
 279 struct page *get_read_data_page(struct inode *inode, pgoff_t index,
 280                                                 int rw, bool for_write)
 281 {
 282         struct address_space *mapping = inode->i_mapping;
 283         struct dnode_of_data dn;
 284         struct page *page;
 285         struct extent_info ei;
 286         int err;
 287         struct f2fs_io_info fio = {
 288                 .sbi = F2FS_I_SB(inode),
 289                 .type = DATA,
 290                 .rw = rw,
 291                 .encrypted_page = NULL,
 292         };
 293
 294         if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
 295                 return read_mapping_page(mapping, index, NULL);
 296
 297         page = f2fs_grab_cache_page(mapping, index, for_write);
 298         if (!page)
 299                 return ERR_PTR(-ENOMEM);
 300
 301         if (f2fs_lookup_extent_cache(inode, index, &ei)) {
 302                 dn.data_blkaddr = ei.blk + index - ei.fofs;
 303                 goto got_it;
 304         }
 305
 306         set_new_dnode(&dn, inode, NULL, NULL, 0);
 307         err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
 308         if (err)
 309                 goto put_err;
 310         f2fs_put_dnode(&dn);
 311
 312         if (unlikely(dn.data_blkaddr == NULL_ADDR)) {
 313                 err = -ENOENT;
 314                 goto put_err;
 315         }
 316 got_it:
 317         if (PageUptodate(page)) {
 318                 unlock_page(page);
 319                 return page;
 320         }
 321
 322         /*
 323          * A new dentry page is allocated but not able to be written, since its
 324          * new inode page couldn't be allocated due to -ENOSPC.
 325          * In such the case, its blkaddr can be remained as NEW_ADDR.
 326          * see, f2fs_add_link -> get_new_data_page -> init_inode_metadata.
 327          */
 328         if (dn.data_blkaddr == NEW_ADDR) {
 329                 zero_user_segment(page, 0, PAGE_CACHE_SIZE);
 330                 SetPageUptodate(page);
 331                 unlock_page(page);
 332                 return page;
 333         }
 334
 335         fio.blk_addr = dn.data_blkaddr;
 336         fio.page = page;
 337         err = f2fs_submit_page_bio(&fio);
 338         if (err)
 339                 goto put_err;
 340         return page;
 341
 342 put_err:
 343         f2fs_put_page(page, 1);
 344         return ERR_PTR(err);
 345 }
 346
 347 struct page *find_data_page(struct inode *inode, pgoff_t index)
 348 {
 349         struct address_space *mapping = inode->i_mapping;
 350         struct page *page;
 351
 352         page = find_get_page(mapping, index);
 353         if (page && PageUptodate(page))
 354                 return page;
 355         f2fs_put_page(page, 0);
 356
 357         page = get_read_data_page(inode, index, READ_SYNC, false);
 358         if (IS_ERR(page))
 359                 return page;
 360
 361         if (PageUptodate(page))
 362                 return page;
 363
 364         wait_on_page_locked(page);
 365         if (unlikely(!PageUptodate(page))) {
 366                 f2fs_put_page(page, 0);
 367                 return ERR_PTR(-EIO);
 368         }
 369         return page;
 370 }
 371
 372 /*
 373  * If it tries to access a hole, return an error.
 374  * Because, the callers, functions in dir.c and GC, should be able to know
 375  * whether this page exists or not.
 376  */
 377 struct page *get_lock_data_page(struct inode *inode, pgoff_t index,
 378                                                         bool for_write)
 379 {
 380         struct address_space *mapping = inode->i_mapping;
 381         struct page *page;
 382 repeat:
 383         page = get_read_data_page(inode, index, READ_SYNC, for_write);
 384         if (IS_ERR(page))
 385                 return page;
 386
 387         /* wait for read completion */
 388         lock_page(page);
 389         if (unlikely(!PageUptodate(page))) {
 390                 f2fs_put_page(page, 1);
 391                 return ERR_PTR(-EIO);
 392         }
 393         if (unlikely(page->mapping != mapping)) {
 394                 f2fs_put_page(page, 1);
 395                 goto repeat;
 396         }
 397         return page;
 398 }
 399
 400 /*
 401  * Caller ensures that this data page is never allocated.
 402  * A new zero-filled data page is allocated in the page cache.
 403  *
 404  * Also, caller should grab and release a rwsem by calling f2fs_lock_op() and
 405  * f2fs_unlock_op().
 406  * Note that, ipage is set only by make_empty_dir, and if any error occur,
 407  * ipage should be released by this function.
 408  */
 409 struct page *get_new_data_page(struct inode *inode,
 410                 struct page *ipage, pgoff_t index, bool new_i_size)
 411 {
 412         struct address_space *mapping = inode->i_mapping;
 413         struct page *page;
 414         struct dnode_of_data dn;
 415         int err;
 416 repeat:
 417         page = f2fs_grab_cache_page(mapping, index, true);
 418         if (!page) {
 419                 /*
 420                  * before exiting, we should make sure ipage will be released
 421                  * if any error occur.
 422                  */
 423                 f2fs_put_page(ipage, 1);
 424                 return ERR_PTR(-ENOMEM);
 425         }
 426
 427         set_new_dnode(&dn, inode, ipage, NULL, 0);
 428         err = f2fs_reserve_block(&dn, index);
 429         if (err) {
 430                 f2fs_put_page(page, 1);
 431                 return ERR_PTR(err);
 432         }
 433         if (!ipage)
 434                 f2fs_put_dnode(&dn);
 435
 436         if (PageUptodate(page))
 437                 goto got_it;
 438
 439         if (dn.data_blkaddr == NEW_ADDR) {
 440                 zero_user_segment(page, 0, PAGE_CACHE_SIZE);
 441                 SetPageUptodate(page);
 442         } else {
 443                 f2fs_put_page(page, 1);
 444
 445                 page = get_read_data_page(inode, index, READ_SYNC, true);
 446                 if (IS_ERR(page))
 447                         goto repeat;
 448
 449                 /* wait for read completion */
 450                 lock_page(page);
 451         }
 452 got_it:
 453         if (new_i_size && i_size_read(inode) <
 454                                 ((loff_t)(index + 1) << PAGE_CACHE_SHIFT)) {
 455                 i_size_write(inode, ((loff_t)(index + 1) << PAGE_CACHE_SHIFT));
 456                 /* Only the directory inode sets new_i_size */
 457                 set_inode_flag(F2FS_I(inode), FI_UPDATE_DIR);
 458         }
 459         return page;
 460 }
 461
 462 static int __allocate_data_block(struct dnode_of_data *dn)
 463 {
 464         struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
 465         struct f2fs_inode_info *fi = F2FS_I(dn->inode);
 466         struct f2fs_summary sum;
 467         struct node_info ni;
 468         int seg = CURSEG_WARM_DATA;
 469         pgoff_t fofs;
 470
 471         if (unlikely(is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC)))
 472                 return -EPERM;
 473
 474         dn->data_blkaddr = datablock_addr(dn->node_page, dn->ofs_in_node);
 475         if (dn->data_blkaddr == NEW_ADDR)
 476                 goto alloc;
 477
 478         if (unlikely(!inc_valid_block_count(sbi, dn->inode, 1)))
 479                 return -ENOSPC;
 480
 481 alloc:
 482         get_node_info(sbi, dn->nid, &ni);
 483         set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
 484
 485         if (dn->ofs_in_node == 0 && dn->inode_page == dn->node_page)
 486                 seg = CURSEG_DIRECT_IO;
 487
 488         allocate_data_block(sbi, NULL, dn->data_blkaddr, &dn->data_blkaddr,
 489                                                                 &sum, seg);
 490         set_data_blkaddr(dn);
 491
 492         /* update i_size */
 493         fofs = start_bidx_of_node(ofs_of_node(dn->node_page), fi) +
 494                                                         dn->ofs_in_node;
 495         if (i_size_read(dn->inode) < ((loff_t)(fofs + 1) << PAGE_CACHE_SHIFT))
 496                 i_size_write(dn->inode,
 497                                 ((loff_t)(fofs + 1) << PAGE_CACHE_SHIFT));
 498
 499         /* direct IO doesn't use extent cache to maximize the performance */
 500         f2fs_drop_largest_extent(dn->inode, fofs);
 501
 502         return 0;
 503 }
 504
 505 static void __allocate_data_blocks(struct inode *inode, loff_t offset,
 506                                                         size_t count)
 507 {
 508         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 509         struct dnode_of_data dn;
 510         u64 start = F2FS_BYTES_TO_BLK(offset);
 511         u64 len = F2FS_BYTES_TO_BLK(count);
 512         bool allocated;
 513         u64 end_offset;
 514
 515         while (len) {
 516                 f2fs_balance_fs(sbi);
 517                 f2fs_lock_op(sbi);
 518
 519                 /* When reading holes, we need its node page */
 520                 set_new_dnode(&dn, inode, NULL, NULL, 0);
 521                 if (get_dnode_of_data(&dn, start, ALLOC_NODE))
 522                         goto out;
 523
 524                 allocated = false;
 525                 end_offset = ADDRS_PER_PAGE(dn.node_page, F2FS_I(inode));
 526
 527                 while (dn.ofs_in_node < end_offset && len) {
 528                         block_t blkaddr;
 529
 530                         if (unlikely(f2fs_cp_error(sbi)))
 531                                 goto sync_out;
 532
 533                         blkaddr = datablock_addr(dn.node_page, dn.ofs_in_node);
 534                         if (blkaddr == NULL_ADDR || blkaddr == NEW_ADDR) {
 535                                 if (__allocate_data_block(&dn))
 536                                         goto sync_out;
 537                                 allocated = true;
 538                         }
 539                         len--;
 540                         start++;
 541                         dn.ofs_in_node++;
 542                 }
 543
 544                 if (allocated)
 545                         sync_inode_page(&dn);
 546
 547                 f2fs_put_dnode(&dn);
 548                 f2fs_unlock_op(sbi);
 549         }
 550         return;
 551
 552 sync_out:
 553         if (allocated)
 554                 sync_inode_page(&dn);
 555         f2fs_put_dnode(&dn);
 556 out:
 557         f2fs_unlock_op(sbi);
 558         return;
 559 }
 560
 561 /*
 562  * f2fs_map_blocks() now supported readahead/bmap/rw direct_IO with
 563  * f2fs_map_blocks structure.
 564  * If original data blocks are allocated, then give them to blockdev.
 565  * Otherwise,
 566  *     a. preallocate requested block addresses
 567  *     b. do not use extent cache for better performance
 568  *     c. give the block addresses to blockdev
 569  */
 570 static int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
 571                                                 int create, int flag)
 572 {
 573         unsigned int maxblocks = map->m_len;
 574         struct dnode_of_data dn;
 575         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 576         int mode = create ? ALLOC_NODE : LOOKUP_NODE_RA;
 577         pgoff_t pgofs, end_offset;
 578         int err = 0, ofs = 1;
 579         struct extent_info ei;
 580         bool allocated = false;
 581
 582         map->m_len = 0;
 583         map->m_flags = 0;
 584
 585         /* it only supports block size == page size */
 586         pgofs = (pgoff_t)map->m_lblk;
 587
 588         if (f2fs_lookup_extent_cache(inode, pgofs, &ei)) {
 589                 map->m_pblk = ei.blk + pgofs - ei.fofs;
 590                 map->m_len = min((pgoff_t)maxblocks, ei.fofs + ei.len - pgofs);
 591                 map->m_flags = F2FS_MAP_MAPPED;
 592                 goto out;
 593         }
 594
 595         if (create)
 596                 f2fs_lock_op(F2FS_I_SB(inode));
 597
 598         /* When reading holes, we need its node page */
 599         set_new_dnode(&dn, inode, NULL, NULL, 0);
 600         err = get_dnode_of_data(&dn, pgofs, mode);
 601         if (err) {
 602                 if (err == -ENOENT)
 603                         err = 0;
 604                 goto unlock_out;
 605         }
 606
 607         if (dn.data_blkaddr == NEW_ADDR || dn.data_blkaddr == NULL_ADDR) {
 608                 if (create) {
 609                         if (unlikely(f2fs_cp_error(sbi))) {
 610                                 err = -EIO;
 611                                 goto put_out;
 612                         }
 613                         err = __allocate_data_block(&dn);
 614                         if (err)
 615                                 goto put_out;
 616                         allocated = true;
 617                         map->m_flags = F2FS_MAP_NEW;
 618                 } else {
 619                         if (flag != F2FS_GET_BLOCK_FIEMAP ||
 620                                                 dn.data_blkaddr != NEW_ADDR) {
 621                                 if (flag == F2FS_GET_BLOCK_BMAP)
 622                                         err = -ENOENT;
 623                                 goto put_out;
 624                         }
 625
 626                         /*
 627                          * preallocated unwritten block should be mapped
 628                          * for fiemap.
 629                          */
 630                         if (dn.data_blkaddr == NEW_ADDR)
 631                                 map->m_flags = F2FS_MAP_UNWRITTEN;
 632                 }
 633         }
 634
 635         map->m_flags |= F2FS_MAP_MAPPED;
 636         map->m_pblk = dn.data_blkaddr;
 637         map->m_len = 1;
 638
 639         end_offset = ADDRS_PER_PAGE(dn.node_page, F2FS_I(inode));
 640         dn.ofs_in_node++;
 641         pgofs++;
 642
 643 get_next:
 644         if (dn.ofs_in_node >= end_offset) {
 645                 if (allocated)
 646                         sync_inode_page(&dn);
 647                 allocated = false;
 648                 f2fs_put_dnode(&dn);
 649
 650                 set_new_dnode(&dn, inode, NULL, NULL, 0);
 651                 err = get_dnode_of_data(&dn, pgofs, mode);
 652                 if (err) {
 653                         if (err == -ENOENT)
 654                                 err = 0;
 655                         goto unlock_out;
 656                 }
 657
 658                 end_offset = ADDRS_PER_PAGE(dn.node_page, F2FS_I(inode));
 659         }
 660
 661         if (maxblocks > map->m_len) {
 662                 block_t blkaddr = datablock_addr(dn.node_page, dn.ofs_in_node);
 663
 664                 if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR) {
 665                         if (create) {
 666                                 if (unlikely(f2fs_cp_error(sbi))) {
 667                                         err = -EIO;
 668                                         goto sync_out;
 669                                 }
 670                                 err = __allocate_data_block(&dn);
 671                                 if (err)
 672                                         goto sync_out;
 673                                 allocated = true;
 674                                 map->m_flags |= F2FS_MAP_NEW;
 675                                 blkaddr = dn.data_blkaddr;
 676                         } else {
 677                                 /*
 678                                  * we only merge preallocated unwritten blocks
 679                                  * for fiemap.
 680                                  */
 681                                 if (flag != F2FS_GET_BLOCK_FIEMAP ||
 682                                                 blkaddr != NEW_ADDR)
 683                                         goto sync_out;
 684                         }
 685                 }
 686
 687                 /* Give more consecutive addresses for the readahead */
 688                 if ((map->m_pblk != NEW_ADDR &&
 689                                 blkaddr == (map->m_pblk + ofs)) ||
 690                                 (map->m_pblk == NEW_ADDR &&
 691                                 blkaddr == NEW_ADDR)) {
 692                         ofs++;
 693                         dn.ofs_in_node++;
 694                         pgofs++;
 695                         map->m_len++;
 696                         goto get_next;
 697                 }
 698         }
 699 sync_out:
 700         if (allocated)
 701                 sync_inode_page(&dn);
 702 put_out:
 703         f2fs_put_dnode(&dn);
 704 unlock_out:
 705         if (create)
 706                 f2fs_unlock_op(F2FS_I_SB(inode));
 707 out:
 708         trace_f2fs_map_blocks(inode, map, err);
 709         return err;
 710 }
 711
 712 static int __get_data_block(struct inode *inode, sector_t iblock,
 713                         struct buffer_head *bh, int create, int flag)
 714 {
 715         struct f2fs_map_blocks map;
 716         int ret;
 717
 718         map.m_lblk = iblock;
 719         map.m_len = bh->b_size >> inode->i_blkbits;
 720
 721         ret = f2fs_map_blocks(inode, &map, create, flag);
 722         if (!ret) {
 723                 map_bh(bh, inode->i_sb, map.m_pblk);
 724                 bh->b_state = (bh->b_state & ~F2FS_MAP_FLAGS) | map.m_flags;
 725                 bh->b_size = map.m_len << inode->i_blkbits;
 726         }
 727         return ret;
 728 }
 729
 730 static int get_data_block(struct inode *inode, sector_t iblock,
 731                         struct buffer_head *bh_result, int create, int flag)
 732 {
 733         return __get_data_block(inode, iblock, bh_result, create, flag);
 734 }
 735
 736 static int get_data_block_dio(struct inode *inode, sector_t iblock,
 737                         struct buffer_head *bh_result, int create)
 738 {
 739         return __get_data_block(inode, iblock, bh_result, create,
 740                                                 F2FS_GET_BLOCK_DIO);
 741 }
 742
 743 static int get_data_block_bmap(struct inode *inode, sector_t iblock,
 744                         struct buffer_head *bh_result, int create)
 745 {
 746         return __get_data_block(inode, iblock, bh_result, create,
 747                                                 F2FS_GET_BLOCK_BMAP);
 748 }
 749
 750 static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
 751 {
 752         return (offset >> inode->i_blkbits);
 753 }
 754
 755 static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
 756 {
 757         return (blk << inode->i_blkbits);
 758 }
 759
 760 int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 761                 u64 start, u64 len)
 762 {
 763         struct buffer_head map_bh;
 764         sector_t start_blk, last_blk;
 765         loff_t isize = i_size_read(inode);
 766         u64 logical = 0, phys = 0, size = 0;
 767         u32 flags = 0;
 768         bool past_eof = false, whole_file = false;
 769         int ret = 0;
 770
 771         ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
 772         if (ret)
 773                 return ret;
 774
 775         if (f2fs_has_inline_data(inode)) {
 776                 ret = f2fs_inline_data_fiemap(inode, fieinfo, start, len);
 777                 if (ret != -EAGAIN)
 778                         return ret;
 779         }
 780
 781         mutex_lock(&inode->i_mutex);
 782
 783         if (len >= isize) {
 784                 whole_file = true;
 785                 len = isize;
 786         }
 787
 788         if (logical_to_blk(inode, len) == 0)
 789                 len = blk_to_logical(inode, 1);
 790
 791         start_blk = logical_to_blk(inode, start);
 792         last_blk = logical_to_blk(inode, start + len - 1);
 793 next:
 794         memset(&map_bh, 0, sizeof(struct buffer_head));
 795         map_bh.b_size = len;
 796
 797         ret = get_data_block(inode, start_blk, &map_bh, 0,
 798                                         F2FS_GET_BLOCK_FIEMAP);
 799         if (ret)
 800                 goto out;
 801
 802         /* HOLE */
 803         if (!buffer_mapped(&map_bh)) {
 804                 start_blk++;
 805
 806                 if (!past_eof && blk_to_logical(inode, start_blk) >= isize)
 807                         past_eof = 1;
 808
 809                 if (past_eof && size) {
 810                         flags |= FIEMAP_EXTENT_LAST;
 811                         ret = fiemap_fill_next_extent(fieinfo, logical,
 812                                         phys, size, flags);
 813                 } else if (size) {
 814                         ret = fiemap_fill_next_extent(fieinfo, logical,
 815                                         phys, size, flags);
 816                         size = 0;
 817                 }
 818
 819                 /* if we have holes up to/past EOF then we're done */
 820                 if (start_blk > last_blk || past_eof || ret)
 821                         goto out;
 822         } else {
 823                 if (start_blk > last_blk && !whole_file) {
 824                         ret = fiemap_fill_next_extent(fieinfo, logical,
 825                                         phys, size, flags);
 826                         goto out;
 827                 }
 828
 829                 /*
 830                  * if size != 0 then we know we already have an extent
 831                  * to add, so add it.
 832                  */
 833                 if (size) {
 834                         ret = fiemap_fill_next_extent(fieinfo, logical,
 835                                         phys, size, flags);
 836                         if (ret)
 837                                 goto out;
 838                 }
 839
 840                 logical = blk_to_logical(inode, start_blk);
 841                 phys = blk_to_logical(inode, map_bh.b_blocknr);
 842                 size = map_bh.b_size;
 843                 flags = 0;
 844                 if (buffer_unwritten(&map_bh))
 845                         flags = FIEMAP_EXTENT_UNWRITTEN;
 846
 847                 start_blk += logical_to_blk(inode, size);
 848
 849                 /*
 850                  * If we are past the EOF, then we need to make sure as
 851                  * soon as we find a hole that the last extent we found
 852                  * is marked with FIEMAP_EXTENT_LAST
 853                  */
 854                 if (!past_eof && logical + size >= isize)
 855                         past_eof = true;
 856         }
 857         cond_resched();
 858         if (fatal_signal_pending(current))
 859                 ret = -EINTR;
 860         else
 861                 goto next;
 862 out:
 863         if (ret == 1)
 864                 ret = 0;
 865
 866         mutex_unlock(&inode->i_mutex);
 867         return ret;
 868 }
 869
 870 /*
 871  * This function was originally taken from fs/mpage.c, and customized for f2fs.
 872  * Major change was from block_size == page_size in f2fs by default.
 873  */
 874 static int f2fs_mpage_readpages(struct address_space *mapping,
 875                         struct list_head *pages, struct page *page,
 876                         unsigned nr_pages)
 877 {
 878         struct bio *bio = NULL;
 879         unsigned page_idx;
 880         sector_t last_block_in_bio = 0;
 881         struct inode *inode = mapping->host;
 882         const unsigned blkbits = inode->i_blkbits;
 883         const unsigned blocksize = 1 << blkbits;
 884         sector_t block_in_file;
 885         sector_t last_block;
 886         sector_t last_block_in_file;
 887         sector_t block_nr;
 888         struct block_device *bdev = inode->i_sb->s_bdev;
 889         struct f2fs_map_blocks map;
 890
 891         map.m_pblk = 0;
 892         map.m_lblk = 0;
 893         map.m_len = 0;
 894         map.m_flags = 0;
 895
 896         for (page_idx = 0; nr_pages; page_idx++, nr_pages--) {
 897
 898                 prefetchw(&page->flags);
 899                 if (pages) {
 900                         page = list_entry(pages->prev, struct page, lru);
 901                         list_del(&page->lru);
 902                         if (add_to_page_cache_lru(page, mapping,
 903                                                   page->index, GFP_KERNEL))
 904                                 goto next_page;
 905                 }
 906
 907                 block_in_file = (sector_t)page->index;
 908                 last_block = block_in_file + nr_pages;
 909                 last_block_in_file = (i_size_read(inode) + blocksize - 1) >>
 910                                                                 blkbits;
 911                 if (last_block > last_block_in_file)
 912                         last_block = last_block_in_file;
 913
 914                 /*
 915                  * Map blocks using the previous result first.
 916                  */
 917                 if ((map.m_flags & F2FS_MAP_MAPPED) &&
 918                                 block_in_file > map.m_lblk &&
 919                                 block_in_file < (map.m_lblk + map.m_len))
 920                         goto got_it;
 921
 922                 /*
 923                  * Then do more f2fs_map_blocks() calls until we are
 924                  * done with this page.
 925                  */
 926                 map.m_flags = 0;
 927
 928                 if (block_in_file < last_block) {
 929                         map.m_lblk = block_in_file;
 930                         map.m_len = last_block - block_in_file;
 931
 932                         if (f2fs_map_blocks(inode, &map, 0,
 933                                                         F2FS_GET_BLOCK_READ))
 934                                 goto set_error_page;
 935                 }
 936 got_it:
 937                 if ((map.m_flags & F2FS_MAP_MAPPED)) {
 938                         block_nr = map.m_pblk + block_in_file - map.m_lblk;
 939                         SetPageMappedToDisk(page);
 940
 941                         if (!PageUptodate(page) && !cleancache_get_page(page)) {
 942                                 SetPageUptodate(page);
 943                                 goto confused;
 944                         }
 945                 } else {
 946                         zero_user_segment(page, 0, PAGE_CACHE_SIZE);
 947                         SetPageUptodate(page);
 948                         unlock_page(page);
 949                         goto next_page;
 950                 }
 951
 952                 /*
 953                  * This page will go to BIO.  Do we need to send this
 954                  * BIO off first?
 955                  */
 956                 if (bio && (last_block_in_bio != block_nr - 1)) {
 957 submit_and_realloc:
 958                         submit_bio(READ, bio);
 959                         bio = NULL;
 960                 }
 961                 if (bio == NULL) {
 962                         struct f2fs_crypto_ctx *ctx = NULL;
 963
 964                         if (f2fs_encrypted_inode(inode) &&
 965                                         S_ISREG(inode->i_mode)) {
 966
 967                                 ctx = f2fs_get_crypto_ctx(inode);
 968                                 if (IS_ERR(ctx))
 969                                         goto set_error_page;
 970
 971                                 /* wait the page to be moved by cleaning */
 972                                 f2fs_wait_on_encrypted_page_writeback(
 973                                                 F2FS_I_SB(inode), block_nr);
 974                         }
 975
 976                         bio = bio_alloc(GFP_KERNEL,
 977                                 min_t(int, nr_pages, BIO_MAX_PAGES));
 978                         if (!bio) {
 979                                 if (ctx)
 980                                         f2fs_release_crypto_ctx(ctx);
 981                                 goto set_error_page;
 982                         }
 983                         bio->bi_bdev = bdev;
 984                         bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(block_nr);
 985                         bio->bi_end_io = f2fs_read_end_io;
 986                         bio->bi_private = ctx;
 987                 }
 988
 989                 if (bio_add_page(bio, page, blocksize, 0) < blocksize)
 990                         goto submit_and_realloc;
 991
 992                 last_block_in_bio = block_nr;
 993                 goto next_page;
 994 set_error_page:
 995                 SetPageError(page);
 996                 zero_user_segment(page, 0, PAGE_CACHE_SIZE);
 997                 unlock_page(page);
 998                 goto next_page;
 999 confused:
1000                 if (bio) {
1001                         submit_bio(READ, bio);
1002                         bio = NULL;
1003                 }
1004                 unlock_page(page);
1005 next_page:
1006                 if (pages)
1007                         page_cache_release(page);
1008         }
1009         BUG_ON(pages && !list_empty(pages));
1010         if (bio)
1011                 submit_bio(READ, bio);
1012         return 0;
1013 }
1014
1015 static int f2fs_read_data_page(struct file *file, struct page *page)
1016 {
1017         struct inode *inode = page->mapping->host;
1018         int ret = -EAGAIN;
1019
1020         trace_f2fs_readpage(page, DATA);
1021
1022         /* If the file has inline data, try to read it directly */
1023         if (f2fs_has_inline_data(inode))
1024                 ret = f2fs_read_inline_data(inode, page);
1025         if (ret == -EAGAIN)
1026                 ret = f2fs_mpage_readpages(page->mapping, NULL, page, 1);
1027         return ret;
1028 }
1029
1030 static int f2fs_read_data_pages(struct file *file,
1031                         struct address_space *mapping,
1032                         struct list_head *pages, unsigned nr_pages)
1033 {
1034         struct inode *inode = file->f_mapping->host;
1035         struct page *page = list_entry(pages->prev, struct page, lru);
1036
1037         trace_f2fs_readpages(inode, page, nr_pages);
1038
1039         /* If the file has inline data, skip readpages */
1040         if (f2fs_has_inline_data(inode))
1041                 return 0;
1042
1043         return f2fs_mpage_readpages(mapping, pages, NULL, nr_pages);
1044 }
1045
1046 int do_write_data_page(struct f2fs_io_info *fio)
1047 {
1048         struct page *page = fio->page;
1049         struct inode *inode = page->mapping->host;
1050         struct dnode_of_data dn;
1051         int err = 0;
1052
1053         set_new_dnode(&dn, inode, NULL, NULL, 0);
1054         err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
1055         if (err)
1056                 return err;
1057
1058         fio->blk_addr = dn.data_blkaddr;
1059
1060         /* This page is already truncated */
1061         if (fio->blk_addr == NULL_ADDR) {
1062                 ClearPageUptodate(page);
1063                 goto out_writepage;
1064         }
1065
1066         if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) {
1067
1068                 /* wait for GCed encrypted page writeback */
1069                 f2fs_wait_on_encrypted_page_writeback(F2FS_I_SB(inode),
1070                                                         fio->blk_addr);
1071
1072                 fio->encrypted_page = f2fs_encrypt(inode, fio->page);
1073                 if (IS_ERR(fio->encrypted_page)) {
1074                         err = PTR_ERR(fio->encrypted_page);
1075                         goto out_writepage;
1076                 }
1077         }
1078
1079         set_page_writeback(page);
1080
1081         /*
1082          * If current allocation needs SSR,
1083          * it had better in-place writes for updated data.
1084          */
1085         if (unlikely(fio->blk_addr != NEW_ADDR &&
1086                         !is_cold_data(page) &&
1087                         need_inplace_update(inode))) {
1088                 rewrite_data_page(fio);
1089                 set_inode_flag(F2FS_I(inode), FI_UPDATE_WRITE);
1090                 trace_f2fs_do_write_data_page(page, IPU);
1091         } else {
1092                 write_data_page(&dn, fio);
1093                 set_data_blkaddr(&dn);
1094                 f2fs_update_extent_cache(&dn);
1095                 trace_f2fs_do_write_data_page(page, OPU);
1096                 set_inode_flag(F2FS_I(inode), FI_APPEND_WRITE);
1097                 if (page->index == 0)
1098                         set_inode_flag(F2FS_I(inode), FI_FIRST_BLOCK_WRITTEN);
1099         }
1100 out_writepage:
1101         f2fs_put_dnode(&dn);
1102         return err;
1103 }
1104
1105 static int f2fs_write_data_page(struct page *page,
1106                                         struct writeback_control *wbc)
1107 {
1108         struct inode *inode = page->mapping->host;
1109         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1110         loff_t i_size = i_size_read(inode);
1111         const pgoff_t end_index = ((unsigned long long) i_size)
1112                                                         >> PAGE_CACHE_SHIFT;
1113         unsigned offset = 0;
1114         bool need_balance_fs = false;
1115         int err = 0;
1116         struct f2fs_io_info fio = {
1117                 .sbi = sbi,
1118                 .type = DATA,
1119                 .rw = (wbc->sync_mode == WB_SYNC_ALL) ? WRITE_SYNC : WRITE,
1120                 .page = page,
1121                 .encrypted_page = NULL,
1122         };
1123
1124         trace_f2fs_writepage(page, DATA);
1125
1126         if (page->index < end_index)
1127                 goto write;
1128
1129         /*
1130          * If the offset is out-of-range of file size,
1131          * this page does not have to be written to disk.
1132          */
1133         offset = i_size & (PAGE_CACHE_SIZE - 1);
1134         if ((page->index >= end_index + 1) || !offset)
1135                 goto out;
1136
1137         zero_user_segment(page, offset, PAGE_CACHE_SIZE);
1138 write:
1139         if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
1140                 goto redirty_out;
1141         if (f2fs_is_drop_cache(inode))
1142                 goto out;
1143         if (f2fs_is_volatile_file(inode) && !wbc->for_reclaim &&
1144                         available_free_memory(sbi, BASE_CHECK))
1145                 goto redirty_out;
1146
1147         /* Dentry blocks are controlled by checkpoint */
1148         if (S_ISDIR(inode->i_mode)) {
1149                 if (unlikely(f2fs_cp_error(sbi)))
1150                         goto redirty_out;
1151                 err = do_write_data_page(&fio);
1152                 goto done;
1153         }
1154
1155         /* we should bypass data pages to proceed the kworkder jobs */
1156         if (unlikely(f2fs_cp_error(sbi))) {
1157                 SetPageError(page);
1158                 goto out;
1159         }
1160
1161         if (!wbc->for_reclaim)
1162                 need_balance_fs = true;
1163         else if (has_not_enough_free_secs(sbi, 0))
1164                 goto redirty_out;
1165
1166         err = -EAGAIN;
1167         f2fs_lock_op(sbi);
1168         if (f2fs_has_inline_data(inode))
1169                 err = f2fs_write_inline_data(inode, page);
1170         if (err == -EAGAIN)
1171                 err = do_write_data_page(&fio);
1172         f2fs_unlock_op(sbi);
1173 done:
1174         if (err && err != -ENOENT)
1175                 goto redirty_out;
1176
1177         clear_cold_data(page);
1178 out:
1179         inode_dec_dirty_pages(inode);
1180         if (err)
1181                 ClearPageUptodate(page);
1182         unlock_page(page);
1183         if (need_balance_fs)
1184                 f2fs_balance_fs(sbi);
1185         if (wbc->for_reclaim)
1186                 f2fs_submit_merged_bio(sbi, DATA, WRITE);
1187         return 0;
1188
1189 redirty_out:
1190         redirty_page_for_writepage(wbc, page);
1191         return AOP_WRITEPAGE_ACTIVATE;
1192 }
1193
1194 static int __f2fs_writepage(struct page *page, struct writeback_control *wbc,
1195                         void *data)
1196 {
1197         struct address_space *mapping = data;
1198         int ret = mapping->a_ops->writepage(page, wbc);
1199         mapping_set_error(mapping, ret);
1200         return ret;
1201 }
1202
1203 /*
1204  * This function was copied from write_cche_pages from mm/page-writeback.c.
1205  * The major change is making write step of cold data page separately from
1206  * warm/hot data page.
1207  */
1208 static int f2fs_write_cache_pages(struct address_space *mapping,
1209                         struct writeback_control *wbc, writepage_t writepage,
1210                         void *data)
1211 {
1212         int ret = 0;
1213         int done = 0;
1214         struct pagevec pvec;
1215         int nr_pages;
1216         pgoff_t uninitialized_var(writeback_index);
1217         pgoff_t index;
1218         pgoff_t end;            /* Inclusive */
1219         pgoff_t done_index;
1220         int cycled;
1221         int range_whole = 0;
1222         int tag;
1223         int step = 0;
1224
1225         pagevec_init(&pvec, 0);
1226 next:
1227         if (wbc->range_cyclic) {
1228                 writeback_index = mapping->writeback_index; /* prev offset */
1229                 index = writeback_index;
1230                 if (index == 0)
1231                         cycled = 1;
1232                 else
1233                         cycled = 0;
1234                 end = -1;
1235         } else {
1236                 index = wbc->range_start >> PAGE_CACHE_SHIFT;
1237                 end = wbc->range_end >> PAGE_CACHE_SHIFT;
1238                 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
1239                         range_whole = 1;
1240                 cycled = 1; /* ignore range_cyclic tests */
1241         }
1242         if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
1243                 tag = PAGECACHE_TAG_TOWRITE;
1244         else
1245                 tag = PAGECACHE_TAG_DIRTY;
1246 retry:
1247         if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
1248                 tag_pages_for_writeback(mapping, index, end);
1249         done_index = index;
1250         while (!done && (index <= end)) {
1251                 int i;
1252
1253                 nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
1254                               min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1);
1255                 if (nr_pages == 0)
1256                         break;
1257
1258                 for (i = 0; i < nr_pages; i++) {
1259                         struct page *page = pvec.pages[i];
1260
1261                         if (page->index > end) {
1262                                 done = 1;
1263                                 break;
1264                         }
1265
1266                         done_index = page->index;
1267
1268                         lock_page(page);
1269
1270                         if (unlikely(page->mapping != mapping)) {
1271 continue_unlock:
1272                                 unlock_page(page);
1273                                 continue;
1274                         }
1275
1276                         if (!PageDirty(page)) {
1277                                 /* someone wrote it for us */
1278                                 goto continue_unlock;
1279                         }
1280
1281                         if (step == is_cold_data(page))
1282                                 goto continue_unlock;
1283
1284                         if (PageWriteback(page)) {
1285                                 if (wbc->sync_mode != WB_SYNC_NONE)
1286                                         f2fs_wait_on_page_writeback(page, DATA);
1287                                 else
1288                                         goto continue_unlock;
1289                         }
1290
1291                         BUG_ON(PageWriteback(page));
1292                         if (!clear_page_dirty_for_io(page))
1293                                 goto continue_unlock;
1294
1295                         ret = (*writepage)(page, wbc, data);
1296                         if (unlikely(ret)) {
1297                                 if (ret == AOP_WRITEPAGE_ACTIVATE) {
1298                                         unlock_page(page);
1299                                         ret = 0;
1300                                 } else {
1301                                         done_index = page->index + 1;
1302                                         done = 1;
1303                                         break;
1304                                 }
1305                         }
1306
1307                         if (--wbc->nr_to_write <= 0 &&
1308                             wbc->sync_mode == WB_SYNC_NONE) {
1309                                 done = 1;
1310                                 break;
1311                         }
1312                 }
1313                 pagevec_release(&pvec);
1314                 cond_resched();
1315         }
1316
1317         if (step < 1) {
1318                 step++;
1319                 goto next;
1320         }
1321
1322         if (!cycled && !done) {
1323                 cycled = 1;
1324                 index = 0;
1325                 end = writeback_index - 1;
1326                 goto retry;
1327         }
1328         if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1329                 mapping->writeback_index = done_index;
1330
1331         return ret;
1332 }
1333
1334 static int f2fs_write_data_pages(struct address_space *mapping,
1335                             struct writeback_control *wbc)
1336 {
1337         struct inode *inode = mapping->host;
1338         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1339         bool locked = false;
1340         int ret;
1341         long diff;
1342
1343         trace_f2fs_writepages(mapping->host, wbc, DATA);
1344
1345         /* deal with chardevs and other special file */
1346         if (!mapping->a_ops->writepage)
1347                 return 0;
1348
1349         /* skip writing if there is no dirty page in this inode */
1350         if (!get_dirty_pages(inode) && wbc->sync_mode == WB_SYNC_NONE)
1351                 return 0;
1352
1353         if (S_ISDIR(inode->i_mode) && wbc->sync_mode == WB_SYNC_NONE &&
1354                         get_dirty_pages(inode) < nr_pages_to_skip(sbi, DATA) &&
1355                         available_free_memory(sbi, DIRTY_DENTS))
1356                 goto skip_write;
1357
1358         /* during POR, we don't need to trigger writepage at all. */
1359         if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
1360                 goto skip_write;
1361
1362         diff = nr_pages_to_write(sbi, DATA, wbc);
1363
1364         if (!S_ISDIR(inode->i_mode)) {
1365                 mutex_lock(&sbi->writepages);
1366                 locked = true;
1367         }
1368         ret = f2fs_write_cache_pages(mapping, wbc, __f2fs_writepage, mapping);
1369         f2fs_submit_merged_bio(sbi, DATA, WRITE);
1370         if (locked)
1371                 mutex_unlock(&sbi->writepages);
1372
1373         remove_dirty_dir_inode(inode);
1374
1375         wbc->nr_to_write = max((long)0, wbc->nr_to_write - diff);
1376         return ret;
1377
1378 skip_write:
1379         wbc->pages_skipped += get_dirty_pages(inode);
1380         return 0;
1381 }
1382
1383 static void f2fs_write_failed(struct address_space *mapping, loff_t to)
1384 {
1385         struct inode *inode = mapping->host;
1386
1387         if (to > inode->i_size) {
1388                 truncate_pagecache(inode, inode->i_size);
1389                 truncate_blocks(inode, inode->i_size, true);
1390         }
1391 }
1392
1393 static int f2fs_write_begin(struct file *file, struct address_space *mapping,
1394                 loff_t pos, unsigned len, unsigned flags,
1395                 struct page **pagep, void **fsdata)
1396 {
1397         struct inode *inode = mapping->host;
1398         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1399         struct page *page = NULL;
1400         struct page *ipage;
1401         pgoff_t index = ((unsigned long long) pos) >> PAGE_CACHE_SHIFT;
1402         struct dnode_of_data dn;
1403         int err = 0;
1404
1405         trace_android_fs_datawrite_start(inode, pos, len,
1406                                          current->pid, current->comm);
1407         trace_f2fs_write_begin(inode, pos, len, flags);
1408
1409         f2fs_balance_fs(sbi);
1410
1411         /*
1412          * We should check this at this moment to avoid deadlock on inode page
1413          * and #0 page. The locking rule for inline_data conversion should be:
1414          * lock_page(page #0) -> lock_page(inode_page)
1415          */
1416         if (index != 0) {
1417                 err = f2fs_convert_inline_inode(inode);
1418                 if (err)
1419                         goto fail;
1420         }
1421 repeat:
1422         page = grab_cache_page_write_begin(mapping, index, flags);
1423         if (!page) {
1424                 err = -ENOMEM;
1425                 goto fail;
1426         }
1427
1428         *pagep = page;
1429
1430         f2fs_lock_op(sbi);
1431
1432         /* check inline_data */
1433         ipage = get_node_page(sbi, inode->i_ino);
1434         if (IS_ERR(ipage)) {
1435                 err = PTR_ERR(ipage);
1436                 goto unlock_fail;
1437         }
1438
1439         set_new_dnode(&dn, inode, ipage, ipage, 0);
1440
1441         if (f2fs_has_inline_data(inode)) {
1442                 if (pos + len <= MAX_INLINE_DATA) {
1443                         read_inline_data(page, ipage);
1444                         set_inode_flag(F2FS_I(inode), FI_DATA_EXIST);
1445                         sync_inode_page(&dn);
1446                         goto put_next;
1447                 }
1448                 err = f2fs_convert_inline_page(&dn, page);
1449                 if (err)
1450                         goto put_fail;
1451         }
1452
1453         err = f2fs_get_block(&dn, index);
1454         if (err)
1455                 goto put_fail;
1456 put_next:
1457         f2fs_put_dnode(&dn);
1458         f2fs_unlock_op(sbi);
1459
1460         f2fs_wait_on_page_writeback(page, DATA);
1461
1462         /* wait for GCed encrypted page writeback */
1463         if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
1464                 f2fs_wait_on_encrypted_page_writeback(sbi, dn.data_blkaddr);
1465
1466         if (len == PAGE_CACHE_SIZE)
1467                 goto out_update;
1468         if (PageUptodate(page))
1469                 goto out_clear;
1470
1471         if ((pos & PAGE_CACHE_MASK) >= i_size_read(inode)) {
1472                 unsigned start = pos & (PAGE_CACHE_SIZE - 1);
1473                 unsigned end = start + len;
1474
1475                 /* Reading beyond i_size is simple: memset to zero */
1476                 zero_user_segments(page, 0, start, end, PAGE_CACHE_SIZE);
1477                 goto out_update;
1478         }
1479
1480         if (dn.data_blkaddr == NEW_ADDR) {
1481                 zero_user_segment(page, 0, PAGE_CACHE_SIZE);
1482         } else {
1483                 struct f2fs_io_info fio = {
1484                         .sbi = sbi,
1485                         .type = DATA,
1486                         .rw = READ_SYNC,
1487                         .blk_addr = dn.data_blkaddr,
1488                         .page = page,
1489                         .encrypted_page = NULL,
1490                 };
1491                 err = f2fs_submit_page_bio(&fio);
1492                 if (err)
1493                         goto fail;
1494
1495                 lock_page(page);
1496                 if (unlikely(!PageUptodate(page))) {
1497                         err = -EIO;
1498                         goto fail;
1499                 }
1500                 if (unlikely(page->mapping != mapping)) {
1501                         f2fs_put_page(page, 1);
1502                         goto repeat;
1503                 }
1504
1505                 /* avoid symlink page */
1506                 if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) {
1507                         err = f2fs_decrypt_one(inode, page);
1508                         if (err)
1509                                 goto fail;
1510                 }
1511         }
1512 out_update:
1513         SetPageUptodate(page);
1514 out_clear:
1515         clear_cold_data(page);
1516         return 0;
1517
1518 put_fail:
1519         f2fs_put_dnode(&dn);
1520 unlock_fail:
1521         f2fs_unlock_op(sbi);
1522 fail:
1523         f2fs_put_page(page, 1);
1524         f2fs_write_failed(mapping, pos + len);
1525         return err;
1526 }
1527
1528 static int f2fs_write_end(struct file *file,
1529                         struct address_space *mapping,
1530                         loff_t pos, unsigned len, unsigned copied,
1531                         struct page *page, void *fsdata)
1532 {
1533         struct inode *inode = page->mapping->host;
1534
1535         trace_android_fs_datawrite_end(inode, pos, len);
1536         trace_f2fs_write_end(inode, pos, len, copied);
1537
1538         set_page_dirty(page);
1539
1540         if (pos + copied > i_size_read(inode)) {
1541                 i_size_write(inode, pos + copied);
1542                 mark_inode_dirty(inode);
1543                 update_inode_page(inode);
1544         }
1545
1546         f2fs_put_page(page, 1);
1547         return copied;
1548 }
1549
1550 static int check_direct_IO(struct inode *inode, struct iov_iter *iter,
1551                            loff_t offset)
1552 {
1553         unsigned blocksize_mask = inode->i_sb->s_blocksize - 1;
1554
1555         if (offset & blocksize_mask)
1556                 return -EINVAL;
1557
1558         if (iov_iter_alignment(iter) & blocksize_mask)
1559                 return -EINVAL;
1560
1561         return 0;
1562 }
1563
1564 static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter,
1565                               loff_t offset)
1566 {
1567         struct file *file = iocb->ki_filp;
1568         struct address_space *mapping = file->f_mapping;
1569         struct inode *inode = mapping->host;
1570         size_t count = iov_iter_count(iter);
1571         int err;
1572
1573         /* we don't need to use inline_data strictly */
1574         if (f2fs_has_inline_data(inode)) {
1575                 err = f2fs_convert_inline_inode(inode);
1576                 if (err)
1577                         return err;
1578         }
1579
1580         if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
1581                 return 0;
1582
1583         err = check_direct_IO(inode, iter, offset);
1584         if (err)
1585                 return err;
1586
1587         trace_f2fs_direct_IO_enter(inode, offset, count, iov_iter_rw(iter));
1588
1589         if (trace_android_fs_dataread_start_enabled() &&
1590             (iov_iter_rw(iter) == READ))
1591                 trace_android_fs_dataread_start(inode, offset,
1592                                                 count, current->pid,
1593                                                 current->comm);
1594         if (trace_android_fs_datawrite_start_enabled() &&
1595             (iov_iter_rw(iter) == WRITE))
1596                 trace_android_fs_datawrite_start(inode, offset, count,
1597                                                  current->pid, current->comm);
1598
1599         if (iov_iter_rw(iter) == WRITE) {
1600                 __allocate_data_blocks(inode, offset, count);
1601                 if (unlikely(f2fs_cp_error(F2FS_I_SB(inode)))) {
1602                         err = -EIO;
1603                         goto out;
1604                 }
1605         }
1606
1607         err = blockdev_direct_IO(iocb, inode, iter, offset, get_data_block_dio);
1608 out:
1609         if (err < 0 && iov_iter_rw(iter) == WRITE)
1610                 f2fs_write_failed(mapping, offset + count);
1611
1612         if (trace_android_fs_dataread_start_enabled() &&
1613             (iov_iter_rw(iter) == READ))
1614                 trace_android_fs_dataread_end(inode, offset, count);
1615         if (trace_android_fs_datawrite_start_enabled() &&
1616             (iov_iter_rw(iter) == WRITE))
1617                 trace_android_fs_datawrite_end(inode, offset, count);
1618
1619         trace_f2fs_direct_IO_exit(inode, offset, count, iov_iter_rw(iter), err);
1620
1621         return err;
1622 }
1623
1624 void f2fs_invalidate_page(struct page *page, unsigned int offset,
1625                                                         unsigned int length)
1626 {
1627         struct inode *inode = page->mapping->host;
1628         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1629
1630         if (inode->i_ino >= F2FS_ROOT_INO(sbi) &&
1631                 (offset % PAGE_CACHE_SIZE || length != PAGE_CACHE_SIZE))
1632                 return;
1633
1634         if (PageDirty(page)) {
1635                 if (inode->i_ino == F2FS_META_INO(sbi))
1636                         dec_page_count(sbi, F2FS_DIRTY_META);
1637                 else if (inode->i_ino == F2FS_NODE_INO(sbi))
1638                         dec_page_count(sbi, F2FS_DIRTY_NODES);
1639                 else
1640                         inode_dec_dirty_pages(inode);
1641         }
1642
1643         /* This is atomic written page, keep Private */
1644         if (IS_ATOMIC_WRITTEN_PAGE(page))
1645                 return;
1646
1647         ClearPagePrivate(page);
1648 }
1649
1650 int f2fs_release_page(struct page *page, gfp_t wait)
1651 {
1652         /* If this is dirty page, keep PagePrivate */
1653         if (PageDirty(page))
1654                 return 0;
1655
1656         /* This is atomic written page, keep Private */
1657         if (IS_ATOMIC_WRITTEN_PAGE(page))
1658                 return 0;
1659
1660         ClearPagePrivate(page);
1661         return 1;
1662 }
1663
1664 static int f2fs_set_data_page_dirty(struct page *page)
1665 {
1666         struct address_space *mapping = page->mapping;
1667         struct inode *inode = mapping->host;
1668
1669         trace_f2fs_set_page_dirty(page, DATA);
1670
1671         SetPageUptodate(page);
1672
1673         if (f2fs_is_atomic_file(inode)) {
1674                 if (!IS_ATOMIC_WRITTEN_PAGE(page)) {
1675                         register_inmem_page(inode, page);
1676                         return 1;
1677                 }
1678                 /*
1679                  * Previously, this page has been registered, we just
1680                  * return here.
1681                  */
1682                 return 0;
1683         }
1684
1685         if (!PageDirty(page)) {
1686                 __set_page_dirty_nobuffers(page);
1687                 update_dirty_page(inode, page);
1688                 return 1;
1689         }
1690         return 0;
1691 }
1692
1693 static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
1694 {
1695         struct inode *inode = mapping->host;
1696
1697         if (f2fs_has_inline_data(inode))
1698                 return 0;
1699
1700         /* make sure allocating whole blocks */
1701         if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
1702                 filemap_write_and_wait(mapping);
1703
1704         return generic_block_bmap(mapping, block, get_data_block_bmap);
1705 }
1706
1707 const struct address_space_operations f2fs_dblock_aops = {
1708         .readpage       = f2fs_read_data_page,
1709         .readpages      = f2fs_read_data_pages,
1710         .writepage      = f2fs_write_data_page,
1711         .writepages     = f2fs_write_data_pages,
1712         .write_begin    = f2fs_write_begin,
1713         .write_end      = f2fs_write_end,
1714         .set_page_dirty = f2fs_set_data_page_dirty,
1715         .invalidatepage = f2fs_invalidate_page,
1716         .releasepage    = f2fs_release_page,
1717         .direct_IO      = f2fs_direct_IO,
1718         .bmap           = f2fs_bmap,
1719 };