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/mm.h>
  23 #include <linux/memcontrol.h>
  24 #include <linux/cleancache.h>
  25 #include <linux/sched/signal.h>
  26
  27 #include "f2fs.h"
  28 #include "node.h"
  29 #include "segment.h"
  30 #include "trace.h"
  31 #include <trace/events/f2fs.h>
  32
  33 static bool __is_cp_guaranteed(struct page *page)
  34 {
  35         struct address_space *mapping = page->mapping;
  36         struct inode *inode;
  37         struct f2fs_sb_info *sbi;
  38
  39         if (!mapping)
  40                 return false;
  41
  42         inode = mapping->host;
  43         sbi = F2FS_I_SB(inode);
  44
  45         if (inode->i_ino == F2FS_META_INO(sbi) ||
  46                         inode->i_ino ==  F2FS_NODE_INO(sbi) ||
  47                         S_ISDIR(inode->i_mode) ||
  48                         is_cold_data(page))
  49                 return true;
  50         return false;
  51 }
  52
  53 static void f2fs_read_end_io(struct bio *bio)
  54 {
  55         struct bio_vec *bvec;
  56         int i;
  57
  58 #ifdef CONFIG_F2FS_FAULT_INJECTION
  59         if (time_to_inject(F2FS_P_SB(bio->bi_io_vec->bv_page), FAULT_IO)) {
  60                 f2fs_show_injection_info(FAULT_IO);
  61                 bio->bi_error = -EIO;
  62         }
  63 #endif
  64
  65         if (f2fs_bio_encrypted(bio)) {
  66                 if (bio->bi_error) {
  67                         fscrypt_release_ctx(bio->bi_private);
  68                 } else {
  69                         fscrypt_decrypt_bio_pages(bio->bi_private, bio);
  70                         return;
  71                 }
  72         }
  73
  74         bio_for_each_segment_all(bvec, bio, i) {
  75                 struct page *page = bvec->bv_page;
  76
  77                 if (!bio->bi_error) {
  78                         if (!PageUptodate(page))
  79                                 SetPageUptodate(page);
  80                 } else {
  81                         ClearPageUptodate(page);
  82                         SetPageError(page);
  83                 }
  84                 unlock_page(page);
  85         }
  86         bio_put(bio);
  87 }
  88
  89 static void f2fs_write_end_io(struct bio *bio)
  90 {
  91         struct f2fs_sb_info *sbi = bio->bi_private;
  92         struct bio_vec *bvec;
  93         int i;
  94
  95         bio_for_each_segment_all(bvec, bio, i) {
  96                 struct page *page = bvec->bv_page;
  97                 enum count_type type = WB_DATA_TYPE(page);
  98
  99                 if (IS_DUMMY_WRITTEN_PAGE(page)) {
 100                         set_page_private(page, (unsigned long)NULL);
 101                         ClearPagePrivate(page);
 102                         unlock_page(page);
 103                         mempool_free(page, sbi->write_io_dummy);
 104
 105                         if (unlikely(bio->bi_error))
 106                                 f2fs_stop_checkpoint(sbi, true);
 107                         continue;
 108                 }
 109
 110                 fscrypt_pullback_bio_page(&page, true);
 111
 112                 if (unlikely(bio->bi_error)) {
 113                         mapping_set_error(page->mapping, -EIO);
 114                         f2fs_stop_checkpoint(sbi, true);
 115                 }
 116                 dec_page_count(sbi, type);
 117                 clear_cold_data(page);
 118                 end_page_writeback(page);
 119         }
 120         if (!get_pages(sbi, F2FS_WB_CP_DATA) &&
 121                                 wq_has_sleeper(&sbi->cp_wait))
 122                 wake_up(&sbi->cp_wait);
 123
 124         bio_put(bio);
 125 }
 126
 127 /*
 128  * Return true, if pre_bio's bdev is same as its target device.
 129  */
 130 struct block_device *f2fs_target_device(struct f2fs_sb_info *sbi,
 131                                 block_t blk_addr, struct bio *bio)
 132 {
 133         struct block_device *bdev = sbi->sb->s_bdev;
 134         int i;
 135
 136         for (i = 0; i < sbi->s_ndevs; i++) {
 137                 if (FDEV(i).start_blk <= blk_addr &&
 138                                         FDEV(i).end_blk >= blk_addr) {
 139                         blk_addr -= FDEV(i).start_blk;
 140                         bdev = FDEV(i).bdev;
 141                         break;
 142                 }
 143         }
 144         if (bio) {
 145                 bio->bi_bdev = bdev;
 146                 bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(blk_addr);
 147         }
 148         return bdev;
 149 }
 150
 151 int f2fs_target_device_index(struct f2fs_sb_info *sbi, block_t blkaddr)
 152 {
 153         int i;
 154
 155         for (i = 0; i < sbi->s_ndevs; i++)
 156                 if (FDEV(i).start_blk <= blkaddr && FDEV(i).end_blk >= blkaddr)
 157                         return i;
 158         return 0;
 159 }
 160
 161 static bool __same_bdev(struct f2fs_sb_info *sbi,
 162                                 block_t blk_addr, struct bio *bio)
 163 {
 164         return f2fs_target_device(sbi, blk_addr, NULL) == bio->bi_bdev;
 165 }
 166
 167 /*
 168  * Low-level block read/write IO operations.
 169  */
 170 static struct bio *__bio_alloc(struct f2fs_sb_info *sbi, block_t blk_addr,
 171                                 int npages, bool is_read)
 172 {
 173         struct bio *bio;
 174
 175         bio = f2fs_bio_alloc(npages);
 176
 177         f2fs_target_device(sbi, blk_addr, bio);
 178         bio->bi_end_io = is_read ? f2fs_read_end_io : f2fs_write_end_io;
 179         bio->bi_private = is_read ? NULL : sbi;
 180
 181         return bio;
 182 }
 183
 184 static inline void __submit_bio(struct f2fs_sb_info *sbi,
 185                                 struct bio *bio, enum page_type type)
 186 {
 187         if (!is_read_io(bio_op(bio))) {
 188                 unsigned int start;
 189
 190                 if (f2fs_sb_mounted_blkzoned(sbi->sb) &&
 191                         current->plug && (type == DATA || type == NODE))
 192                         blk_finish_plug(current->plug);
 193
 194                 if (type != DATA && type != NODE)
 195                         goto submit_io;
 196
 197                 start = bio->bi_iter.bi_size >> F2FS_BLKSIZE_BITS;
 198                 start %= F2FS_IO_SIZE(sbi);
 199
 200                 if (start == 0)
 201                         goto submit_io;
 202
 203                 /* fill dummy pages */
 204                 for (; start < F2FS_IO_SIZE(sbi); start++) {
 205                         struct page *page =
 206                                 mempool_alloc(sbi->write_io_dummy,
 207                                         GFP_NOIO | __GFP_ZERO | __GFP_NOFAIL);
 208                         f2fs_bug_on(sbi, !page);
 209
 210                         SetPagePrivate(page);
 211                         set_page_private(page, (unsigned long)DUMMY_WRITTEN_PAGE);
 212                         lock_page(page);
 213                         if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE)
 214                                 f2fs_bug_on(sbi, 1);
 215                 }
 216                 /*
 217                  * In the NODE case, we lose next block address chain. So, we
 218                  * need to do checkpoint in f2fs_sync_file.
 219                  */
 220                 if (type == NODE)
 221                         set_sbi_flag(sbi, SBI_NEED_CP);
 222         }
 223 submit_io:
 224         if (is_read_io(bio_op(bio)))
 225                 trace_f2fs_submit_read_bio(sbi->sb, type, bio);
 226         else
 227                 trace_f2fs_submit_write_bio(sbi->sb, type, bio);
 228         submit_bio(bio);
 229 }
 230
 231 static void __submit_merged_bio(struct f2fs_bio_info *io)
 232 {
 233         struct f2fs_io_info *fio = &io->fio;
 234
 235         if (!io->bio)
 236                 return;
 237
 238         bio_set_op_attrs(io->bio, fio->op, fio->op_flags);
 239
 240         if (is_read_io(fio->op))
 241                 trace_f2fs_prepare_read_bio(io->sbi->sb, fio->type, io->bio);
 242         else
 243                 trace_f2fs_prepare_write_bio(io->sbi->sb, fio->type, io->bio);
 244
 245         __submit_bio(io->sbi, io->bio, fio->type);
 246         io->bio = NULL;
 247 }
 248
 249 static bool __has_merged_page(struct f2fs_bio_info *io,
 250                                 struct inode *inode, nid_t ino, pgoff_t idx)
 251 {
 252         struct bio_vec *bvec;
 253         struct page *target;
 254         int i;
 255
 256         if (!io->bio)
 257                 return false;
 258
 259         if (!inode && !ino)
 260                 return true;
 261
 262         bio_for_each_segment_all(bvec, io->bio, i) {
 263
 264                 if (bvec->bv_page->mapping)
 265                         target = bvec->bv_page;
 266                 else
 267                         target = fscrypt_control_page(bvec->bv_page);
 268
 269                 if (idx != target->index)
 270                         continue;
 271
 272                 if (inode && inode == target->mapping->host)
 273                         return true;
 274                 if (ino && ino == ino_of_node(target))
 275                         return true;
 276         }
 277
 278         return false;
 279 }
 280
 281 static bool has_merged_page(struct f2fs_sb_info *sbi, struct inode *inode,
 282                                 nid_t ino, pgoff_t idx, enum page_type type)
 283 {
 284         enum page_type btype = PAGE_TYPE_OF_BIO(type);
 285         struct f2fs_bio_info *io = &sbi->write_io[btype];
 286         bool ret;
 287
 288         down_read(&io->io_rwsem);
 289         ret = __has_merged_page(io, inode, ino, idx);
 290         up_read(&io->io_rwsem);
 291         return ret;
 292 }
 293
 294 static void __f2fs_submit_merged_bio(struct f2fs_sb_info *sbi,
 295                                 struct inode *inode, nid_t ino, pgoff_t idx,
 296                                 enum page_type type, int rw)
 297 {
 298         enum page_type btype = PAGE_TYPE_OF_BIO(type);
 299         struct f2fs_bio_info *io;
 300
 301         io = is_read_io(rw) ? &sbi->read_io : &sbi->write_io[btype];
 302
 303         down_write(&io->io_rwsem);
 304
 305         if (!__has_merged_page(io, inode, ino, idx))
 306                 goto out;
 307
 308         /* change META to META_FLUSH in the checkpoint procedure */
 309         if (type >= META_FLUSH) {
 310                 io->fio.type = META_FLUSH;
 311                 io->fio.op = REQ_OP_WRITE;
 312                 io->fio.op_flags = REQ_META | REQ_PRIO;
 313                 if (!test_opt(sbi, NOBARRIER))
 314                         io->fio.op_flags |= REQ_PREFLUSH | REQ_FUA;
 315         }
 316         __submit_merged_bio(io);
 317 out:
 318         up_write(&io->io_rwsem);
 319 }
 320
 321 void f2fs_submit_merged_bio(struct f2fs_sb_info *sbi, enum page_type type,
 322                                                                         int rw)
 323 {
 324         __f2fs_submit_merged_bio(sbi, NULL, 0, 0, type, rw);
 325 }
 326
 327 void f2fs_submit_merged_bio_cond(struct f2fs_sb_info *sbi,
 328                                 struct inode *inode, nid_t ino, pgoff_t idx,
 329                                 enum page_type type, int rw)
 330 {
 331         if (has_merged_page(sbi, inode, ino, idx, type))
 332                 __f2fs_submit_merged_bio(sbi, inode, ino, idx, type, rw);
 333 }
 334
 335 void f2fs_flush_merged_bios(struct f2fs_sb_info *sbi)
 336 {
 337         f2fs_submit_merged_bio(sbi, DATA, WRITE);
 338         f2fs_submit_merged_bio(sbi, NODE, WRITE);
 339         f2fs_submit_merged_bio(sbi, META, WRITE);
 340 }
 341
 342 /*
 343  * Fill the locked page with data located in the block address.
 344  * Return unlocked page.
 345  */
 346 int f2fs_submit_page_bio(struct f2fs_io_info *fio)
 347 {
 348         struct bio *bio;
 349         struct page *page = fio->encrypted_page ?
 350                         fio->encrypted_page : fio->page;
 351
 352         trace_f2fs_submit_page_bio(page, fio);
 353         f2fs_trace_ios(fio, 0);
 354
 355         /* Allocate a new bio */
 356         bio = __bio_alloc(fio->sbi, fio->new_blkaddr, 1, is_read_io(fio->op));
 357
 358         if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
 359                 bio_put(bio);
 360                 return -EFAULT;
 361         }
 362         bio_set_op_attrs(bio, fio->op, fio->op_flags);
 363
 364         __submit_bio(fio->sbi, bio, fio->type);
 365         return 0;
 366 }
 367
 368 int f2fs_submit_page_mbio(struct f2fs_io_info *fio)
 369 {
 370         struct f2fs_sb_info *sbi = fio->sbi;
 371         enum page_type btype = PAGE_TYPE_OF_BIO(fio->type);
 372         struct f2fs_bio_info *io;
 373         bool is_read = is_read_io(fio->op);
 374         struct page *bio_page;
 375         int err = 0;
 376
 377         io = is_read ? &sbi->read_io : &sbi->write_io[btype];
 378
 379         if (fio->old_blkaddr != NEW_ADDR)
 380                 verify_block_addr(sbi, fio->old_blkaddr);
 381         verify_block_addr(sbi, fio->new_blkaddr);
 382
 383         bio_page = fio->encrypted_page ? fio->encrypted_page : fio->page;
 384
 385         /* set submitted = 1 as a return value */
 386         fio->submitted = 1;
 387
 388         if (!is_read)
 389                 inc_page_count(sbi, WB_DATA_TYPE(bio_page));
 390
 391         down_write(&io->io_rwsem);
 392
 393         if (io->bio && (io->last_block_in_bio != fio->new_blkaddr - 1 ||
 394             (io->fio.op != fio->op || io->fio.op_flags != fio->op_flags) ||
 395                         !__same_bdev(sbi, fio->new_blkaddr, io->bio)))
 396                 __submit_merged_bio(io);
 397 alloc_new:
 398         if (io->bio == NULL) {
 399                 if ((fio->type == DATA || fio->type == NODE) &&
 400                                 fio->new_blkaddr & F2FS_IO_SIZE_MASK(sbi)) {
 401                         err = -EAGAIN;
 402                         if (!is_read)
 403                                 dec_page_count(sbi, WB_DATA_TYPE(bio_page));
 404                         goto out_fail;
 405                 }
 406                 io->bio = __bio_alloc(sbi, fio->new_blkaddr,
 407                                                 BIO_MAX_PAGES, is_read);
 408                 io->fio = *fio;
 409         }
 410
 411         if (bio_add_page(io->bio, bio_page, PAGE_SIZE, 0) <
 412                                                         PAGE_SIZE) {
 413                 __submit_merged_bio(io);
 414                 goto alloc_new;
 415         }
 416
 417         io->last_block_in_bio = fio->new_blkaddr;
 418         f2fs_trace_ios(fio, 0);
 419 out_fail:
 420         up_write(&io->io_rwsem);
 421         trace_f2fs_submit_page_mbio(fio->page, fio);
 422         return err;
 423 }
 424
 425 static void __set_data_blkaddr(struct dnode_of_data *dn)
 426 {
 427         struct f2fs_node *rn = F2FS_NODE(dn->node_page);
 428         __le32 *addr_array;
 429
 430         /* Get physical address of data block */
 431         addr_array = blkaddr_in_node(rn);
 432         addr_array[dn->ofs_in_node] = cpu_to_le32(dn->data_blkaddr);
 433 }
 434
 435 /*
 436  * Lock ordering for the change of data block address:
 437  * ->data_page
 438  *  ->node_page
 439  *    update block addresses in the node page
 440  */
 441 void set_data_blkaddr(struct dnode_of_data *dn)
 442 {
 443         f2fs_wait_on_page_writeback(dn->node_page, NODE, true);
 444         __set_data_blkaddr(dn);
 445         if (set_page_dirty(dn->node_page))
 446                 dn->node_changed = true;
 447 }
 448
 449 void f2fs_update_data_blkaddr(struct dnode_of_data *dn, block_t blkaddr)
 450 {
 451         dn->data_blkaddr = blkaddr;
 452         set_data_blkaddr(dn);
 453         f2fs_update_extent_cache(dn);
 454 }
 455
 456 /* dn->ofs_in_node will be returned with up-to-date last block pointer */
 457 int reserve_new_blocks(struct dnode_of_data *dn, blkcnt_t count)
 458 {
 459         struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
 460
 461         if (!count)
 462                 return 0;
 463
 464         if (unlikely(is_inode_flag_set(dn->inode, FI_NO_ALLOC)))
 465                 return -EPERM;
 466         if (unlikely(!inc_valid_block_count(sbi, dn->inode, &count)))
 467                 return -ENOSPC;
 468
 469         trace_f2fs_reserve_new_blocks(dn->inode, dn->nid,
 470                                                 dn->ofs_in_node, count);
 471
 472         f2fs_wait_on_page_writeback(dn->node_page, NODE, true);
 473
 474         for (; count > 0; dn->ofs_in_node++) {
 475                 block_t blkaddr =
 476                         datablock_addr(dn->node_page, dn->ofs_in_node);
 477                 if (blkaddr == NULL_ADDR) {
 478                         dn->data_blkaddr = NEW_ADDR;
 479                         __set_data_blkaddr(dn);
 480                         count--;
 481                 }
 482         }
 483
 484         if (set_page_dirty(dn->node_page))
 485                 dn->node_changed = true;
 486         return 0;
 487 }
 488
 489 /* Should keep dn->ofs_in_node unchanged */
 490 int reserve_new_block(struct dnode_of_data *dn)
 491 {
 492         unsigned int ofs_in_node = dn->ofs_in_node;
 493         int ret;
 494
 495         ret = reserve_new_blocks(dn, 1);
 496         dn->ofs_in_node = ofs_in_node;
 497         return ret;
 498 }
 499
 500 int f2fs_reserve_block(struct dnode_of_data *dn, pgoff_t index)
 501 {
 502         bool need_put = dn->inode_page ? false : true;
 503         int err;
 504
 505         err = get_dnode_of_data(dn, index, ALLOC_NODE);
 506         if (err)
 507                 return err;
 508
 509         if (dn->data_blkaddr == NULL_ADDR)
 510                 err = reserve_new_block(dn);
 511         if (err || need_put)
 512                 f2fs_put_dnode(dn);
 513         return err;
 514 }
 515
 516 int f2fs_get_block(struct dnode_of_data *dn, pgoff_t index)
 517 {
 518         struct extent_info ei  = {0,0,0};
 519         struct inode *inode = dn->inode;
 520
 521         if (f2fs_lookup_extent_cache(inode, index, &ei)) {
 522                 dn->data_blkaddr = ei.blk + index - ei.fofs;
 523                 return 0;
 524         }
 525
 526         return f2fs_reserve_block(dn, index);
 527 }
 528
 529 struct page *get_read_data_page(struct inode *inode, pgoff_t index,
 530                                                 int op_flags, bool for_write)
 531 {
 532         struct address_space *mapping = inode->i_mapping;
 533         struct dnode_of_data dn;
 534         struct page *page;
 535         struct extent_info ei = {0,0,0};
 536         int err;
 537         struct f2fs_io_info fio = {
 538                 .sbi = F2FS_I_SB(inode),
 539                 .type = DATA,
 540                 .op = REQ_OP_READ,
 541                 .op_flags = op_flags,
 542                 .encrypted_page = NULL,
 543         };
 544
 545         if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
 546                 return read_mapping_page(mapping, index, NULL);
 547
 548         page = f2fs_grab_cache_page(mapping, index, for_write);
 549         if (!page)
 550                 return ERR_PTR(-ENOMEM);
 551
 552         if (f2fs_lookup_extent_cache(inode, index, &ei)) {
 553                 dn.data_blkaddr = ei.blk + index - ei.fofs;
 554                 goto got_it;
 555         }
 556
 557         set_new_dnode(&dn, inode, NULL, NULL, 0);
 558         err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
 559         if (err)
 560                 goto put_err;
 561         f2fs_put_dnode(&dn);
 562
 563         if (unlikely(dn.data_blkaddr == NULL_ADDR)) {
 564                 err = -ENOENT;
 565                 goto put_err;
 566         }
 567 got_it:
 568         if (PageUptodate(page)) {
 569                 unlock_page(page);
 570                 return page;
 571         }
 572
 573         /*
 574          * A new dentry page is allocated but not able to be written, since its
 575          * new inode page couldn't be allocated due to -ENOSPC.
 576          * In such the case, its blkaddr can be remained as NEW_ADDR.
 577          * see, f2fs_add_link -> get_new_data_page -> init_inode_metadata.
 578          */
 579         if (dn.data_blkaddr == NEW_ADDR) {
 580                 zero_user_segment(page, 0, PAGE_SIZE);
 581                 if (!PageUptodate(page))
 582                         SetPageUptodate(page);
 583                 unlock_page(page);
 584                 return page;
 585         }
 586
 587         fio.new_blkaddr = fio.old_blkaddr = dn.data_blkaddr;
 588         fio.page = page;
 589         err = f2fs_submit_page_bio(&fio);
 590         if (err)
 591                 goto put_err;
 592         return page;
 593
 594 put_err:
 595         f2fs_put_page(page, 1);
 596         return ERR_PTR(err);
 597 }
 598
 599 struct page *find_data_page(struct inode *inode, pgoff_t index)
 600 {
 601         struct address_space *mapping = inode->i_mapping;
 602         struct page *page;
 603
 604         page = find_get_page(mapping, index);
 605         if (page && PageUptodate(page))
 606                 return page;
 607         f2fs_put_page(page, 0);
 608
 609         page = get_read_data_page(inode, index, 0, false);
 610         if (IS_ERR(page))
 611                 return page;
 612
 613         if (PageUptodate(page))
 614                 return page;
 615
 616         wait_on_page_locked(page);
 617         if (unlikely(!PageUptodate(page))) {
 618                 f2fs_put_page(page, 0);
 619                 return ERR_PTR(-EIO);
 620         }
 621         return page;
 622 }
 623
 624 /*
 625  * If it tries to access a hole, return an error.
 626  * Because, the callers, functions in dir.c and GC, should be able to know
 627  * whether this page exists or not.
 628  */
 629 struct page *get_lock_data_page(struct inode *inode, pgoff_t index,
 630                                                         bool for_write)
 631 {
 632         struct address_space *mapping = inode->i_mapping;
 633         struct page *page;
 634 repeat:
 635         page = get_read_data_page(inode, index, 0, for_write);
 636         if (IS_ERR(page))
 637                 return page;
 638
 639         /* wait for read completion */
 640         lock_page(page);
 641         if (unlikely(page->mapping != mapping)) {
 642                 f2fs_put_page(page, 1);
 643                 goto repeat;
 644         }
 645         if (unlikely(!PageUptodate(page))) {
 646                 f2fs_put_page(page, 1);
 647                 return ERR_PTR(-EIO);
 648         }
 649         return page;
 650 }
 651
 652 /*
 653  * Caller ensures that this data page is never allocated.
 654  * A new zero-filled data page is allocated in the page cache.
 655  *
 656  * Also, caller should grab and release a rwsem by calling f2fs_lock_op() and
 657  * f2fs_unlock_op().
 658  * Note that, ipage is set only by make_empty_dir, and if any error occur,
 659  * ipage should be released by this function.
 660  */
 661 struct page *get_new_data_page(struct inode *inode,
 662                 struct page *ipage, pgoff_t index, bool new_i_size)
 663 {
 664         struct address_space *mapping = inode->i_mapping;
 665         struct page *page;
 666         struct dnode_of_data dn;
 667         int err;
 668
 669         page = f2fs_grab_cache_page(mapping, index, true);
 670         if (!page) {
 671                 /*
 672                  * before exiting, we should make sure ipage will be released
 673                  * if any error occur.
 674                  */
 675                 f2fs_put_page(ipage, 1);
 676                 return ERR_PTR(-ENOMEM);
 677         }
 678
 679         set_new_dnode(&dn, inode, ipage, NULL, 0);
 680         err = f2fs_reserve_block(&dn, index);
 681         if (err) {
 682                 f2fs_put_page(page, 1);
 683                 return ERR_PTR(err);
 684         }
 685         if (!ipage)
 686                 f2fs_put_dnode(&dn);
 687
 688         if (PageUptodate(page))
 689                 goto got_it;
 690
 691         if (dn.data_blkaddr == NEW_ADDR) {
 692                 zero_user_segment(page, 0, PAGE_SIZE);
 693                 if (!PageUptodate(page))
 694                         SetPageUptodate(page);
 695         } else {
 696                 f2fs_put_page(page, 1);
 697
 698                 /* if ipage exists, blkaddr should be NEW_ADDR */
 699                 f2fs_bug_on(F2FS_I_SB(inode), ipage);
 700                 page = get_lock_data_page(inode, index, true);
 701                 if (IS_ERR(page))
 702                         return page;
 703         }
 704 got_it:
 705         if (new_i_size && i_size_read(inode) <
 706                                 ((loff_t)(index + 1) << PAGE_SHIFT))
 707                 f2fs_i_size_write(inode, ((loff_t)(index + 1) << PAGE_SHIFT));
 708         return page;
 709 }
 710
 711 static int __allocate_data_block(struct dnode_of_data *dn)
 712 {
 713         struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
 714         struct f2fs_summary sum;
 715         struct node_info ni;
 716         pgoff_t fofs;
 717         blkcnt_t count = 1;
 718
 719         if (unlikely(is_inode_flag_set(dn->inode, FI_NO_ALLOC)))
 720                 return -EPERM;
 721
 722         dn->data_blkaddr = datablock_addr(dn->node_page, dn->ofs_in_node);
 723         if (dn->data_blkaddr == NEW_ADDR)
 724                 goto alloc;
 725
 726         if (unlikely(!inc_valid_block_count(sbi, dn->inode, &count)))
 727                 return -ENOSPC;
 728
 729 alloc:
 730         get_node_info(sbi, dn->nid, &ni);
 731         set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
 732
 733         allocate_data_block(sbi, NULL, dn->data_blkaddr, &dn->data_blkaddr,
 734                                                 &sum, CURSEG_WARM_DATA);
 735         set_data_blkaddr(dn);
 736
 737         /* update i_size */
 738         fofs = start_bidx_of_node(ofs_of_node(dn->node_page), dn->inode) +
 739                                                         dn->ofs_in_node;
 740         if (i_size_read(dn->inode) < ((loff_t)(fofs + 1) << PAGE_SHIFT))
 741                 f2fs_i_size_write(dn->inode,
 742                                 ((loff_t)(fofs + 1) << PAGE_SHIFT));
 743         return 0;
 744 }
 745
 746 static inline bool __force_buffered_io(struct inode *inode, int rw)
 747 {
 748         return ((f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) ||
 749                         (rw == WRITE && test_opt(F2FS_I_SB(inode), LFS)) ||
 750                         F2FS_I_SB(inode)->s_ndevs);
 751 }
 752
 753 int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from)
 754 {
 755         struct inode *inode = file_inode(iocb->ki_filp);
 756         struct f2fs_map_blocks map;
 757         int err = 0;
 758
 759         if (is_inode_flag_set(inode, FI_NO_PREALLOC))
 760                 return 0;
 761
 762         map.m_lblk = F2FS_BLK_ALIGN(iocb->ki_pos);
 763         map.m_len = F2FS_BYTES_TO_BLK(iocb->ki_pos + iov_iter_count(from));
 764         if (map.m_len > map.m_lblk)
 765                 map.m_len -= map.m_lblk;
 766         else
 767                 map.m_len = 0;
 768
 769         map.m_next_pgofs = NULL;
 770
 771         if (iocb->ki_flags & IOCB_DIRECT) {
 772                 err = f2fs_convert_inline_inode(inode);
 773                 if (err)
 774                         return err;
 775                 return f2fs_map_blocks(inode, &map, 1,
 776                         __force_buffered_io(inode, WRITE) ?
 777                                 F2FS_GET_BLOCK_PRE_AIO :
 778                                 F2FS_GET_BLOCK_PRE_DIO);
 779         }
 780         if (iocb->ki_pos + iov_iter_count(from) > MAX_INLINE_DATA) {
 781                 err = f2fs_convert_inline_inode(inode);
 782                 if (err)
 783                         return err;
 784         }
 785         if (!f2fs_has_inline_data(inode))
 786                 return f2fs_map_blocks(inode, &map, 1, F2FS_GET_BLOCK_PRE_AIO);
 787         return err;
 788 }
 789
 790 /*
 791  * f2fs_map_blocks() now supported readahead/bmap/rw direct_IO with
 792  * f2fs_map_blocks structure.
 793  * If original data blocks are allocated, then give them to blockdev.
 794  * Otherwise,
 795  *     a. preallocate requested block addresses
 796  *     b. do not use extent cache for better performance
 797  *     c. give the block addresses to blockdev
 798  */
 799 int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
 800                                                 int create, int flag)
 801 {
 802         unsigned int maxblocks = map->m_len;
 803         struct dnode_of_data dn;
 804         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 805         int mode = create ? ALLOC_NODE : LOOKUP_NODE;
 806         pgoff_t pgofs, end_offset, end;
 807         int err = 0, ofs = 1;
 808         unsigned int ofs_in_node, last_ofs_in_node;
 809         blkcnt_t prealloc;
 810         struct extent_info ei = {0,0,0};
 811         block_t blkaddr;
 812
 813         if (!maxblocks)
 814                 return 0;
 815
 816         map->m_len = 0;
 817         map->m_flags = 0;
 818
 819         /* it only supports block size == page size */
 820         pgofs = (pgoff_t)map->m_lblk;
 821         end = pgofs + maxblocks;
 822
 823         if (!create && f2fs_lookup_extent_cache(inode, pgofs, &ei)) {
 824                 map->m_pblk = ei.blk + pgofs - ei.fofs;
 825                 map->m_len = min((pgoff_t)maxblocks, ei.fofs + ei.len - pgofs);
 826                 map->m_flags = F2FS_MAP_MAPPED;
 827                 goto out;
 828         }
 829
 830 next_dnode:
 831         if (create)
 832                 f2fs_lock_op(sbi);
 833
 834         /* When reading holes, we need its node page */
 835         set_new_dnode(&dn, inode, NULL, NULL, 0);
 836         err = get_dnode_of_data(&dn, pgofs, mode);
 837         if (err) {
 838                 if (flag == F2FS_GET_BLOCK_BMAP)
 839                         map->m_pblk = 0;
 840                 if (err == -ENOENT) {
 841                         err = 0;
 842                         if (map->m_next_pgofs)
 843                                 *map->m_next_pgofs =
 844                                         get_next_page_offset(&dn, pgofs);
 845                 }
 846                 goto unlock_out;
 847         }
 848
 849         prealloc = 0;
 850         last_ofs_in_node = ofs_in_node = dn.ofs_in_node;
 851         end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
 852
 853 next_block:
 854         blkaddr = datablock_addr(dn.node_page, dn.ofs_in_node);
 855
 856         if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR) {
 857                 if (create) {
 858                         if (unlikely(f2fs_cp_error(sbi))) {
 859                                 err = -EIO;
 860                                 goto sync_out;
 861                         }
 862                         if (flag == F2FS_GET_BLOCK_PRE_AIO) {
 863                                 if (blkaddr == NULL_ADDR) {
 864                                         prealloc++;
 865                                         last_ofs_in_node = dn.ofs_in_node;
 866                                 }
 867                         } else {
 868                                 err = __allocate_data_block(&dn);
 869                                 if (!err)
 870                                         set_inode_flag(inode, FI_APPEND_WRITE);
 871                         }
 872                         if (err)
 873                                 goto sync_out;
 874                         map->m_flags |= F2FS_MAP_NEW;
 875                         blkaddr = dn.data_blkaddr;
 876                 } else {
 877                         if (flag == F2FS_GET_BLOCK_BMAP) {
 878                                 map->m_pblk = 0;
 879                                 goto sync_out;
 880                         }
 881                         if (flag == F2FS_GET_BLOCK_FIEMAP &&
 882                                                 blkaddr == NULL_ADDR) {
 883                                 if (map->m_next_pgofs)
 884                                         *map->m_next_pgofs = pgofs + 1;
 885                         }
 886                         if (flag != F2FS_GET_BLOCK_FIEMAP ||
 887                                                 blkaddr != NEW_ADDR)
 888                                 goto sync_out;
 889                 }
 890         }
 891
 892         if (flag == F2FS_GET_BLOCK_PRE_AIO)
 893                 goto skip;
 894
 895         if (map->m_len == 0) {
 896                 /* preallocated unwritten block should be mapped for fiemap. */
 897                 if (blkaddr == NEW_ADDR)
 898                         map->m_flags |= F2FS_MAP_UNWRITTEN;
 899                 map->m_flags |= F2FS_MAP_MAPPED;
 900
 901                 map->m_pblk = blkaddr;
 902                 map->m_len = 1;
 903         } else if ((map->m_pblk != NEW_ADDR &&
 904                         blkaddr == (map->m_pblk + ofs)) ||
 905                         (map->m_pblk == NEW_ADDR && blkaddr == NEW_ADDR) ||
 906                         flag == F2FS_GET_BLOCK_PRE_DIO) {
 907                 ofs++;
 908                 map->m_len++;
 909         } else {
 910                 goto sync_out;
 911         }
 912
 913 skip:
 914         dn.ofs_in_node++;
 915         pgofs++;
 916
 917         /* preallocate blocks in batch for one dnode page */
 918         if (flag == F2FS_GET_BLOCK_PRE_AIO &&
 919                         (pgofs == end || dn.ofs_in_node == end_offset)) {
 920
 921                 dn.ofs_in_node = ofs_in_node;
 922                 err = reserve_new_blocks(&dn, prealloc);
 923                 if (err)
 924                         goto sync_out;
 925
 926                 map->m_len += dn.ofs_in_node - ofs_in_node;
 927                 if (prealloc && dn.ofs_in_node != last_ofs_in_node + 1) {
 928                         err = -ENOSPC;
 929                         goto sync_out;
 930                 }
 931                 dn.ofs_in_node = end_offset;
 932         }
 933
 934         if (pgofs >= end)
 935                 goto sync_out;
 936         else if (dn.ofs_in_node < end_offset)
 937                 goto next_block;
 938
 939         f2fs_put_dnode(&dn);
 940
 941         if (create) {
 942                 f2fs_unlock_op(sbi);
 943                 f2fs_balance_fs(sbi, dn.node_changed);
 944         }
 945         goto next_dnode;
 946
 947 sync_out:
 948         f2fs_put_dnode(&dn);
 949 unlock_out:
 950         if (create) {
 951                 f2fs_unlock_op(sbi);
 952                 f2fs_balance_fs(sbi, dn.node_changed);
 953         }
 954 out:
 955         trace_f2fs_map_blocks(inode, map, err);
 956         return err;
 957 }
 958
 959 static int __get_data_block(struct inode *inode, sector_t iblock,
 960                         struct buffer_head *bh, int create, int flag,
 961                         pgoff_t *next_pgofs)
 962 {
 963         struct f2fs_map_blocks map;
 964         int err;
 965
 966         map.m_lblk = iblock;
 967         map.m_len = bh->b_size >> inode->i_blkbits;
 968         map.m_next_pgofs = next_pgofs;
 969
 970         err = f2fs_map_blocks(inode, &map, create, flag);
 971         if (!err) {
 972                 map_bh(bh, inode->i_sb, map.m_pblk);
 973                 bh->b_state = (bh->b_state & ~F2FS_MAP_FLAGS) | map.m_flags;
 974                 bh->b_size = (u64)map.m_len << inode->i_blkbits;
 975         }
 976         return err;
 977 }
 978
 979 static int get_data_block(struct inode *inode, sector_t iblock,
 980                         struct buffer_head *bh_result, int create, int flag,
 981                         pgoff_t *next_pgofs)
 982 {
 983         return __get_data_block(inode, iblock, bh_result, create,
 984                                                         flag, next_pgofs);
 985 }
 986
 987 static int get_data_block_dio(struct inode *inode, sector_t iblock,
 988                         struct buffer_head *bh_result, int create)
 989 {
 990         return __get_data_block(inode, iblock, bh_result, create,
 991                                                 F2FS_GET_BLOCK_DIO, NULL);
 992 }
 993
 994 static int get_data_block_bmap(struct inode *inode, sector_t iblock,
 995                         struct buffer_head *bh_result, int create)
 996 {
 997         /* Block number less than F2FS MAX BLOCKS */
 998         if (unlikely(iblock >= F2FS_I_SB(inode)->max_file_blocks))
 999                 return -EFBIG;
1000
1001         return __get_data_block(inode, iblock, bh_result, create,
1002                                                 F2FS_GET_BLOCK_BMAP, NULL);
1003 }
1004
1005 static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
1006 {
1007         return (offset >> inode->i_blkbits);
1008 }
1009
1010 static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
1011 {
1012         return (blk << inode->i_blkbits);
1013 }
1014
1015 int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1016                 u64 start, u64 len)
1017 {
1018         struct buffer_head map_bh;
1019         sector_t start_blk, last_blk;
1020         pgoff_t next_pgofs;
1021         u64 logical = 0, phys = 0, size = 0;
1022         u32 flags = 0;
1023         int ret = 0;
1024
1025         ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC);
1026         if (ret)
1027                 return ret;
1028
1029         if (f2fs_has_inline_data(inode)) {
1030                 ret = f2fs_inline_data_fiemap(inode, fieinfo, start, len);
1031                 if (ret != -EAGAIN)
1032                         return ret;
1033         }
1034
1035         inode_lock(inode);
1036
1037         if (logical_to_blk(inode, len) == 0)
1038                 len = blk_to_logical(inode, 1);
1039
1040         start_blk = logical_to_blk(inode, start);
1041         last_blk = logical_to_blk(inode, start + len - 1);
1042
1043 next:
1044         memset(&map_bh, 0, sizeof(struct buffer_head));
1045         map_bh.b_size = len;
1046
1047         ret = get_data_block(inode, start_blk, &map_bh, 0,
1048                                         F2FS_GET_BLOCK_FIEMAP, &next_pgofs);
1049         if (ret)
1050                 goto out;
1051
1052         /* HOLE */
1053         if (!buffer_mapped(&map_bh)) {
1054                 start_blk = next_pgofs;
1055
1056                 if (blk_to_logical(inode, start_blk) < blk_to_logical(inode,
1057                                         F2FS_I_SB(inode)->max_file_blocks))
1058                         goto prep_next;
1059
1060                 flags |= FIEMAP_EXTENT_LAST;
1061         }
1062
1063         if (size) {
1064                 if (f2fs_encrypted_inode(inode))
1065                         flags |= FIEMAP_EXTENT_DATA_ENCRYPTED;
1066
1067                 ret = fiemap_fill_next_extent(fieinfo, logical,
1068                                 phys, size, flags);
1069         }
1070
1071         if (start_blk > last_blk || ret)
1072                 goto out;
1073
1074         logical = blk_to_logical(inode, start_blk);
1075         phys = blk_to_logical(inode, map_bh.b_blocknr);
1076         size = map_bh.b_size;
1077         flags = 0;
1078         if (buffer_unwritten(&map_bh))
1079                 flags = FIEMAP_EXTENT_UNWRITTEN;
1080
1081         start_blk += logical_to_blk(inode, size);
1082
1083 prep_next:
1084         cond_resched();
1085         if (fatal_signal_pending(current))
1086                 ret = -EINTR;
1087         else
1088                 goto next;
1089 out:
1090         if (ret == 1)
1091                 ret = 0;
1092
1093         inode_unlock(inode);
1094         return ret;
1095 }
1096
1097 static struct bio *f2fs_grab_bio(struct inode *inode, block_t blkaddr,
1098                                  unsigned nr_pages)
1099 {
1100         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1101         struct fscrypt_ctx *ctx = NULL;
1102         struct bio *bio;
1103
1104         if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) {
1105                 ctx = fscrypt_get_ctx(inode, GFP_NOFS);
1106                 if (IS_ERR(ctx))
1107                         return ERR_CAST(ctx);
1108
1109                 /* wait the page to be moved by cleaning */
1110                 f2fs_wait_on_encrypted_page_writeback(sbi, blkaddr);
1111         }
1112
1113         bio = bio_alloc(GFP_KERNEL, min_t(int, nr_pages, BIO_MAX_PAGES));
1114         if (!bio) {
1115                 if (ctx)
1116                         fscrypt_release_ctx(ctx);
1117                 return ERR_PTR(-ENOMEM);
1118         }
1119         f2fs_target_device(sbi, blkaddr, bio);
1120         bio->bi_end_io = f2fs_read_end_io;
1121         bio->bi_private = ctx;
1122
1123         return bio;
1124 }
1125
1126 /*
1127  * This function was originally taken from fs/mpage.c, and customized for f2fs.
1128  * Major change was from block_size == page_size in f2fs by default.
1129  */
1130 static int f2fs_mpage_readpages(struct address_space *mapping,
1131                         struct list_head *pages, struct page *page,
1132                         unsigned nr_pages)
1133 {
1134         struct bio *bio = NULL;
1135         unsigned page_idx;
1136         sector_t last_block_in_bio = 0;
1137         struct inode *inode = mapping->host;
1138         const unsigned blkbits = inode->i_blkbits;
1139         const unsigned blocksize = 1 << blkbits;
1140         sector_t block_in_file;
1141         sector_t last_block;
1142         sector_t last_block_in_file;
1143         sector_t block_nr;
1144         struct f2fs_map_blocks map;
1145
1146         map.m_pblk = 0;
1147         map.m_lblk = 0;
1148         map.m_len = 0;
1149         map.m_flags = 0;
1150         map.m_next_pgofs = NULL;
1151
1152         for (page_idx = 0; nr_pages; page_idx++, nr_pages--) {
1153
1154                 prefetchw(&page->flags);
1155                 if (pages) {
1156                         page = list_last_entry(pages, struct page, lru);
1157                         list_del(&page->lru);
1158                         if (add_to_page_cache_lru(page, mapping,
1159                                                   page->index,
1160                                                   readahead_gfp_mask(mapping)))
1161                                 goto next_page;
1162                 }
1163
1164                 block_in_file = (sector_t)page->index;
1165                 last_block = block_in_file + nr_pages;
1166                 last_block_in_file = (i_size_read(inode) + blocksize - 1) >>
1167                                                                 blkbits;
1168                 if (last_block > last_block_in_file)
1169                         last_block = last_block_in_file;
1170
1171                 /*
1172                  * Map blocks using the previous result first.
1173                  */
1174                 if ((map.m_flags & F2FS_MAP_MAPPED) &&
1175                                 block_in_file > map.m_lblk &&
1176                                 block_in_file < (map.m_lblk + map.m_len))
1177                         goto got_it;
1178
1179                 /*
1180                  * Then do more f2fs_map_blocks() calls until we are
1181                  * done with this page.
1182                  */
1183                 map.m_flags = 0;
1184
1185                 if (block_in_file < last_block) {
1186                         map.m_lblk = block_in_file;
1187                         map.m_len = last_block - block_in_file;
1188
1189                         if (f2fs_map_blocks(inode, &map, 0,
1190                                                 F2FS_GET_BLOCK_READ))
1191                                 goto set_error_page;
1192                 }
1193 got_it:
1194                 if ((map.m_flags & F2FS_MAP_MAPPED)) {
1195                         block_nr = map.m_pblk + block_in_file - map.m_lblk;
1196                         SetPageMappedToDisk(page);
1197
1198                         if (!PageUptodate(page) && !cleancache_get_page(page)) {
1199                                 SetPageUptodate(page);
1200                                 goto confused;
1201                         }
1202                 } else {
1203                         zero_user_segment(page, 0, PAGE_SIZE);
1204                         if (!PageUptodate(page))
1205                                 SetPageUptodate(page);
1206                         unlock_page(page);
1207                         goto next_page;
1208                 }
1209
1210                 /*
1211                  * This page will go to BIO.  Do we need to send this
1212                  * BIO off first?
1213                  */
1214                 if (bio && (last_block_in_bio != block_nr - 1 ||
1215                         !__same_bdev(F2FS_I_SB(inode), block_nr, bio))) {
1216 submit_and_realloc:
1217                         __submit_bio(F2FS_I_SB(inode), bio, DATA);
1218                         bio = NULL;
1219                 }
1220                 if (bio == NULL) {
1221                         bio = f2fs_grab_bio(inode, block_nr, nr_pages);
1222                         if (IS_ERR(bio)) {
1223                                 bio = NULL;
1224                                 goto set_error_page;
1225                         }
1226                         bio_set_op_attrs(bio, REQ_OP_READ, 0);
1227                 }
1228
1229                 if (bio_add_page(bio, page, blocksize, 0) < blocksize)
1230                         goto submit_and_realloc;
1231
1232                 last_block_in_bio = block_nr;
1233                 goto next_page;
1234 set_error_page:
1235                 SetPageError(page);
1236                 zero_user_segment(page, 0, PAGE_SIZE);
1237                 unlock_page(page);
1238                 goto next_page;
1239 confused:
1240                 if (bio) {
1241                         __submit_bio(F2FS_I_SB(inode), bio, DATA);
1242                         bio = NULL;
1243                 }
1244                 unlock_page(page);
1245 next_page:
1246                 if (pages)
1247                         put_page(page);
1248         }
1249         BUG_ON(pages && !list_empty(pages));
1250         if (bio)
1251                 __submit_bio(F2FS_I_SB(inode), bio, DATA);
1252         return 0;
1253 }
1254
1255 static int f2fs_read_data_page(struct file *file, struct page *page)
1256 {
1257         struct inode *inode = page->mapping->host;
1258         int ret = -EAGAIN;
1259
1260         trace_f2fs_readpage(page, DATA);
1261
1262         /* If the file has inline data, try to read it directly */
1263         if (f2fs_has_inline_data(inode))
1264                 ret = f2fs_read_inline_data(inode, page);
1265         if (ret == -EAGAIN)
1266                 ret = f2fs_mpage_readpages(page->mapping, NULL, page, 1);
1267         return ret;
1268 }
1269
1270 static int f2fs_read_data_pages(struct file *file,
1271                         struct address_space *mapping,
1272                         struct list_head *pages, unsigned nr_pages)
1273 {
1274         struct inode *inode = file->f_mapping->host;
1275         struct page *page = list_last_entry(pages, struct page, lru);
1276
1277         trace_f2fs_readpages(inode, page, nr_pages);
1278
1279         /* If the file has inline data, skip readpages */
1280         if (f2fs_has_inline_data(inode))
1281                 return 0;
1282
1283         return f2fs_mpage_readpages(mapping, pages, NULL, nr_pages);
1284 }
1285
1286 int do_write_data_page(struct f2fs_io_info *fio)
1287 {
1288         struct page *page = fio->page;
1289         struct inode *inode = page->mapping->host;
1290         struct dnode_of_data dn;
1291         int err = 0;
1292
1293         set_new_dnode(&dn, inode, NULL, NULL, 0);
1294         err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
1295         if (err)
1296                 return err;
1297
1298         fio->old_blkaddr = dn.data_blkaddr;
1299
1300         /* This page is already truncated */
1301         if (fio->old_blkaddr == NULL_ADDR) {
1302                 ClearPageUptodate(page);
1303                 goto out_writepage;
1304         }
1305
1306         if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode)) {
1307                 gfp_t gfp_flags = GFP_NOFS;
1308
1309                 /* wait for GCed encrypted page writeback */
1310                 f2fs_wait_on_encrypted_page_writeback(F2FS_I_SB(inode),
1311                                                         fio->old_blkaddr);
1312 retry_encrypt:
1313                 fio->encrypted_page = fscrypt_encrypt_page(inode, fio->page,
1314                                                         PAGE_SIZE, 0,
1315                                                         fio->page->index,
1316                                                         gfp_flags);
1317                 if (IS_ERR(fio->encrypted_page)) {
1318                         err = PTR_ERR(fio->encrypted_page);
1319                         if (err == -ENOMEM) {
1320                                 /* flush pending ios and wait for a while */
1321                                 f2fs_flush_merged_bios(F2FS_I_SB(inode));
1322                                 congestion_wait(BLK_RW_ASYNC, HZ/50);
1323                                 gfp_flags |= __GFP_NOFAIL;
1324                                 err = 0;
1325                                 goto retry_encrypt;
1326                         }
1327                         goto out_writepage;
1328                 }
1329         }
1330
1331         set_page_writeback(page);
1332
1333         /*
1334          * If current allocation needs SSR,
1335          * it had better in-place writes for updated data.
1336          */
1337         if (unlikely(fio->old_blkaddr != NEW_ADDR &&
1338                         !is_cold_data(page) &&
1339                         !IS_ATOMIC_WRITTEN_PAGE(page) &&
1340                         need_inplace_update(inode))) {
1341                 rewrite_data_page(fio);
1342                 set_inode_flag(inode, FI_UPDATE_WRITE);
1343                 trace_f2fs_do_write_data_page(page, IPU);
1344         } else {
1345                 write_data_page(&dn, fio);
1346                 trace_f2fs_do_write_data_page(page, OPU);
1347                 set_inode_flag(inode, FI_APPEND_WRITE);
1348                 if (page->index == 0)
1349                         set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
1350         }
1351 out_writepage:
1352         f2fs_put_dnode(&dn);
1353         return err;
1354 }
1355
1356 static int __write_data_page(struct page *page, bool *submitted,
1357                                 struct writeback_control *wbc)
1358 {
1359         struct inode *inode = page->mapping->host;
1360         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1361         loff_t i_size = i_size_read(inode);
1362         const pgoff_t end_index = ((unsigned long long) i_size)
1363                                                         >> PAGE_SHIFT;
1364         loff_t psize = (page->index + 1) << PAGE_SHIFT;
1365         unsigned offset = 0;
1366         bool need_balance_fs = false;
1367         int err = 0;
1368         struct f2fs_io_info fio = {
1369                 .sbi = sbi,
1370                 .type = DATA,
1371                 .op = REQ_OP_WRITE,
1372                 .op_flags = wbc_to_write_flags(wbc),
1373                 .page = page,
1374                 .encrypted_page = NULL,
1375                 .submitted = false,
1376         };
1377
1378         trace_f2fs_writepage(page, DATA);
1379
1380         if (page->index < end_index)
1381                 goto write;
1382
1383         /*
1384          * If the offset is out-of-range of file size,
1385          * this page does not have to be written to disk.
1386          */
1387         offset = i_size & (PAGE_SIZE - 1);
1388         if ((page->index >= end_index + 1) || !offset)
1389                 goto out;
1390
1391         zero_user_segment(page, offset, PAGE_SIZE);
1392 write:
1393         if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
1394                 goto redirty_out;
1395         if (f2fs_is_drop_cache(inode))
1396                 goto out;
1397         /* we should not write 0'th page having journal header */
1398         if (f2fs_is_volatile_file(inode) && (!page->index ||
1399                         (!wbc->for_reclaim &&
1400                         available_free_memory(sbi, BASE_CHECK))))
1401                 goto redirty_out;
1402
1403         /* we should bypass data pages to proceed the kworkder jobs */
1404         if (unlikely(f2fs_cp_error(sbi))) {
1405                 mapping_set_error(page->mapping, -EIO);
1406                 goto out;
1407         }
1408
1409         /* Dentry blocks are controlled by checkpoint */
1410         if (S_ISDIR(inode->i_mode)) {
1411                 err = do_write_data_page(&fio);
1412                 goto done;
1413         }
1414
1415         if (!wbc->for_reclaim)
1416                 need_balance_fs = true;
1417         else if (has_not_enough_free_secs(sbi, 0, 0))
1418                 goto redirty_out;
1419
1420         err = -EAGAIN;
1421         if (f2fs_has_inline_data(inode)) {
1422                 err = f2fs_write_inline_data(inode, page);
1423                 if (!err)
1424                         goto out;
1425         }
1426         f2fs_lock_op(sbi);
1427         if (err == -EAGAIN)
1428                 err = do_write_data_page(&fio);
1429         if (F2FS_I(inode)->last_disk_size < psize)
1430                 F2FS_I(inode)->last_disk_size = psize;
1431         f2fs_unlock_op(sbi);
1432 done:
1433         if (err && err != -ENOENT)
1434                 goto redirty_out;
1435
1436 out:
1437         inode_dec_dirty_pages(inode);
1438         if (err)
1439                 ClearPageUptodate(page);
1440
1441         if (wbc->for_reclaim) {
1442                 f2fs_submit_merged_bio_cond(sbi, inode, 0, page->index,
1443                                                 DATA, WRITE);
1444                 remove_dirty_inode(inode);
1445                 submitted = NULL;
1446         }
1447
1448         unlock_page(page);
1449         f2fs_balance_fs(sbi, need_balance_fs);
1450
1451         if (unlikely(f2fs_cp_error(sbi))) {
1452                 f2fs_submit_merged_bio(sbi, DATA, WRITE);
1453                 submitted = NULL;
1454         }
1455
1456         if (submitted)
1457                 *submitted = fio.submitted;
1458
1459         return 0;
1460
1461 redirty_out:
1462         redirty_page_for_writepage(wbc, page);
1463         if (!err)
1464                 return AOP_WRITEPAGE_ACTIVATE;
1465         unlock_page(page);
1466         return err;
1467 }
1468
1469 static int f2fs_write_data_page(struct page *page,
1470                                         struct writeback_control *wbc)
1471 {
1472         return __write_data_page(page, NULL, wbc);
1473 }
1474
1475 /*
1476  * This function was copied from write_cche_pages from mm/page-writeback.c.
1477  * The major change is making write step of cold data page separately from
1478  * warm/hot data page.
1479  */
1480 static int f2fs_write_cache_pages(struct address_space *mapping,
1481                                         struct writeback_control *wbc)
1482 {
1483         int ret = 0;
1484         int done = 0;
1485         struct pagevec pvec;
1486         int nr_pages;
1487         pgoff_t uninitialized_var(writeback_index);
1488         pgoff_t index;
1489         pgoff_t end;            /* Inclusive */
1490         pgoff_t done_index;
1491         pgoff_t last_idx = ULONG_MAX;
1492         int cycled;
1493         int range_whole = 0;
1494         int tag;
1495
1496         pagevec_init(&pvec, 0);
1497
1498         if (wbc->range_cyclic) {
1499                 writeback_index = mapping->writeback_index; /* prev offset */
1500                 index = writeback_index;
1501                 if (index == 0)
1502                         cycled = 1;
1503                 else
1504                         cycled = 0;
1505                 end = -1;
1506         } else {
1507                 index = wbc->range_start >> PAGE_SHIFT;
1508                 end = wbc->range_end >> PAGE_SHIFT;
1509                 if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
1510                         range_whole = 1;
1511                 cycled = 1; /* ignore range_cyclic tests */
1512         }
1513         if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
1514                 tag = PAGECACHE_TAG_TOWRITE;
1515         else
1516                 tag = PAGECACHE_TAG_DIRTY;
1517 retry:
1518         if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
1519                 tag_pages_for_writeback(mapping, index, end);
1520         done_index = index;
1521         while (!done && (index <= end)) {
1522                 int i;
1523
1524                 nr_pages = pagevec_lookup_tag(&pvec, mapping, &index, tag,
1525                               min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1);
1526                 if (nr_pages == 0)
1527                         break;
1528
1529                 for (i = 0; i < nr_pages; i++) {
1530                         struct page *page = pvec.pages[i];
1531                         bool submitted = false;
1532
1533                         if (page->index > end) {
1534                                 done = 1;
1535                                 break;
1536                         }
1537
1538                         done_index = page->index;
1539
1540                         lock_page(page);
1541
1542                         if (unlikely(page->mapping != mapping)) {
1543 continue_unlock:
1544                                 unlock_page(page);
1545                                 continue;
1546                         }
1547
1548                         if (!PageDirty(page)) {
1549                                 /* someone wrote it for us */
1550                                 goto continue_unlock;
1551                         }
1552
1553                         if (PageWriteback(page)) {
1554                                 if (wbc->sync_mode != WB_SYNC_NONE)
1555                                         f2fs_wait_on_page_writeback(page,
1556                                                                 DATA, true);
1557                                 else
1558                                         goto continue_unlock;
1559                         }
1560
1561                         BUG_ON(PageWriteback(page));
1562                         if (!clear_page_dirty_for_io(page))
1563                                 goto continue_unlock;
1564
1565                         ret = __write_data_page(page, &submitted, wbc);
1566                         if (unlikely(ret)) {
1567                                 /*
1568                                  * keep nr_to_write, since vfs uses this to
1569                                  * get # of written pages.
1570                                  */
1571                                 if (ret == AOP_WRITEPAGE_ACTIVATE) {
1572                                         unlock_page(page);
1573                                         ret = 0;
1574                                         continue;
1575                                 }
1576                                 done_index = page->index + 1;
1577                                 done = 1;
1578                                 break;
1579                         } else if (submitted) {
1580                                 last_idx = page->index;
1581                         }
1582
1583                         if (--wbc->nr_to_write <= 0 &&
1584                             wbc->sync_mode == WB_SYNC_NONE) {
1585                                 done = 1;
1586                                 break;
1587                         }
1588                 }
1589                 pagevec_release(&pvec);
1590                 cond_resched();
1591         }
1592
1593         if (!cycled && !done) {
1594                 cycled = 1;
1595                 index = 0;
1596                 end = writeback_index - 1;
1597                 goto retry;
1598         }
1599         if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1600                 mapping->writeback_index = done_index;
1601
1602         if (last_idx != ULONG_MAX)
1603                 f2fs_submit_merged_bio_cond(F2FS_M_SB(mapping), mapping->host,
1604                                                 0, last_idx, DATA, WRITE);
1605
1606         return ret;
1607 }
1608
1609 static int f2fs_write_data_pages(struct address_space *mapping,
1610                             struct writeback_control *wbc)
1611 {
1612         struct inode *inode = mapping->host;
1613         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1614         struct blk_plug plug;
1615         int ret;
1616
1617         /* deal with chardevs and other special file */
1618         if (!mapping->a_ops->writepage)
1619                 return 0;
1620
1621         /* skip writing if there is no dirty page in this inode */
1622         if (!get_dirty_pages(inode) && wbc->sync_mode == WB_SYNC_NONE)
1623                 return 0;
1624
1625         if (S_ISDIR(inode->i_mode) && wbc->sync_mode == WB_SYNC_NONE &&
1626                         get_dirty_pages(inode) < nr_pages_to_skip(sbi, DATA) &&
1627                         available_free_memory(sbi, DIRTY_DENTS))
1628                 goto skip_write;
1629
1630         /* skip writing during file defragment */
1631         if (is_inode_flag_set(inode, FI_DO_DEFRAG))
1632                 goto skip_write;
1633
1634         /* during POR, we don't need to trigger writepage at all. */
1635         if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
1636                 goto skip_write;
1637
1638         trace_f2fs_writepages(mapping->host, wbc, DATA);
1639
1640         blk_start_plug(&plug);
1641         ret = f2fs_write_cache_pages(mapping, wbc);
1642         blk_finish_plug(&plug);
1643         /*
1644          * if some pages were truncated, we cannot guarantee its mapping->host
1645          * to detect pending bios.
1646          */
1647
1648         remove_dirty_inode(inode);
1649         return ret;
1650
1651 skip_write:
1652         wbc->pages_skipped += get_dirty_pages(inode);
1653         trace_f2fs_writepages(mapping->host, wbc, DATA);
1654         return 0;
1655 }
1656
1657 static void f2fs_write_failed(struct address_space *mapping, loff_t to)
1658 {
1659         struct inode *inode = mapping->host;
1660         loff_t i_size = i_size_read(inode);
1661
1662         if (to > i_size) {
1663                 truncate_pagecache(inode, i_size);
1664                 truncate_blocks(inode, i_size, true);
1665         }
1666 }
1667
1668 static int prepare_write_begin(struct f2fs_sb_info *sbi,
1669                         struct page *page, loff_t pos, unsigned len,
1670                         block_t *blk_addr, bool *node_changed)
1671 {
1672         struct inode *inode = page->mapping->host;
1673         pgoff_t index = page->index;
1674         struct dnode_of_data dn;
1675         struct page *ipage;
1676         bool locked = false;
1677         struct extent_info ei = {0,0,0};
1678         int err = 0;
1679
1680         /*
1681          * we already allocated all the blocks, so we don't need to get
1682          * the block addresses when there is no need to fill the page.
1683          */
1684         if (!f2fs_has_inline_data(inode) && len == PAGE_SIZE &&
1685                         !is_inode_flag_set(inode, FI_NO_PREALLOC))
1686                 return 0;
1687
1688         if (f2fs_has_inline_data(inode) ||
1689                         (pos & PAGE_MASK) >= i_size_read(inode)) {
1690                 f2fs_lock_op(sbi);
1691                 locked = true;
1692         }
1693 restart:
1694         /* check inline_data */
1695         ipage = get_node_page(sbi, inode->i_ino);
1696         if (IS_ERR(ipage)) {
1697                 err = PTR_ERR(ipage);
1698                 goto unlock_out;
1699         }
1700
1701         set_new_dnode(&dn, inode, ipage, ipage, 0);
1702
1703         if (f2fs_has_inline_data(inode)) {
1704                 if (pos + len <= MAX_INLINE_DATA) {
1705                         read_inline_data(page, ipage);
1706                         set_inode_flag(inode, FI_DATA_EXIST);
1707                         if (inode->i_nlink)
1708                                 set_inline_node(ipage);
1709                 } else {
1710                         err = f2fs_convert_inline_page(&dn, page);
1711                         if (err)
1712                                 goto out;
1713                         if (dn.data_blkaddr == NULL_ADDR)
1714                                 err = f2fs_get_block(&dn, index);
1715                 }
1716         } else if (locked) {
1717                 err = f2fs_get_block(&dn, index);
1718         } else {
1719                 if (f2fs_lookup_extent_cache(inode, index, &ei)) {
1720                         dn.data_blkaddr = ei.blk + index - ei.fofs;
1721                 } else {
1722                         /* hole case */
1723                         err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
1724                         if (err || dn.data_blkaddr == NULL_ADDR) {
1725                                 f2fs_put_dnode(&dn);
1726                                 f2fs_lock_op(sbi);
1727                                 locked = true;
1728                                 goto restart;
1729                         }
1730                 }
1731         }
1732
1733         /* convert_inline_page can make node_changed */
1734         *blk_addr = dn.data_blkaddr;
1735         *node_changed = dn.node_changed;
1736 out:
1737         f2fs_put_dnode(&dn);
1738 unlock_out:
1739         if (locked)
1740                 f2fs_unlock_op(sbi);
1741         return err;
1742 }
1743
1744 static int f2fs_write_begin(struct file *file, struct address_space *mapping,
1745                 loff_t pos, unsigned len, unsigned flags,
1746                 struct page **pagep, void **fsdata)
1747 {
1748         struct inode *inode = mapping->host;
1749         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1750         struct page *page = NULL;
1751         pgoff_t index = ((unsigned long long) pos) >> PAGE_SHIFT;
1752         bool need_balance = false;
1753         block_t blkaddr = NULL_ADDR;
1754         int err = 0;
1755
1756         trace_f2fs_write_begin(inode, pos, len, flags);
1757
1758         /*
1759          * We should check this at this moment to avoid deadlock on inode page
1760          * and #0 page. The locking rule for inline_data conversion should be:
1761          * lock_page(page #0) -> lock_page(inode_page)
1762          */
1763         if (index != 0) {
1764                 err = f2fs_convert_inline_inode(inode);
1765                 if (err)
1766                         goto fail;
1767         }
1768 repeat:
1769         /*
1770          * Do not use grab_cache_page_write_begin() to avoid deadlock due to
1771          * wait_for_stable_page. Will wait that below with our IO control.
1772          */
1773         page = pagecache_get_page(mapping, index,
1774                                 FGP_LOCK | FGP_WRITE | FGP_CREAT, GFP_NOFS);
1775         if (!page) {
1776                 err = -ENOMEM;
1777                 goto fail;
1778         }
1779
1780         *pagep = page;
1781
1782         err = prepare_write_begin(sbi, page, pos, len,
1783                                         &blkaddr, &need_balance);
1784         if (err)
1785                 goto fail;
1786
1787         if (need_balance && has_not_enough_free_secs(sbi, 0, 0)) {
1788                 unlock_page(page);
1789                 f2fs_balance_fs(sbi, true);
1790                 lock_page(page);
1791                 if (page->mapping != mapping) {
1792                         /* The page got truncated from under us */
1793                         f2fs_put_page(page, 1);
1794                         goto repeat;
1795                 }
1796         }
1797
1798         f2fs_wait_on_page_writeback(page, DATA, false);
1799
1800         /* wait for GCed encrypted page writeback */
1801         if (f2fs_encrypted_inode(inode) && S_ISREG(inode->i_mode))
1802                 f2fs_wait_on_encrypted_page_writeback(sbi, blkaddr);
1803
1804         if (len == PAGE_SIZE || PageUptodate(page))
1805                 return 0;
1806
1807         if (!(pos & (PAGE_SIZE - 1)) && (pos + len) >= i_size_read(inode)) {
1808                 zero_user_segment(page, len, PAGE_SIZE);
1809                 return 0;
1810         }
1811
1812         if (blkaddr == NEW_ADDR) {
1813                 zero_user_segment(page, 0, PAGE_SIZE);
1814                 SetPageUptodate(page);
1815         } else {
1816                 struct bio *bio;
1817
1818                 bio = f2fs_grab_bio(inode, blkaddr, 1);
1819                 if (IS_ERR(bio)) {
1820                         err = PTR_ERR(bio);
1821                         goto fail;
1822                 }
1823                 bio->bi_opf = REQ_OP_READ;
1824                 if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
1825                         bio_put(bio);
1826                         err = -EFAULT;
1827                         goto fail;
1828                 }
1829
1830                 __submit_bio(sbi, bio, DATA);
1831
1832                 lock_page(page);
1833                 if (unlikely(page->mapping != mapping)) {
1834                         f2fs_put_page(page, 1);
1835                         goto repeat;
1836                 }
1837                 if (unlikely(!PageUptodate(page))) {
1838                         err = -EIO;
1839                         goto fail;
1840                 }
1841         }
1842         return 0;
1843
1844 fail:
1845         f2fs_put_page(page, 1);
1846         f2fs_write_failed(mapping, pos + len);
1847         return err;
1848 }
1849
1850 static int f2fs_write_end(struct file *file,
1851                         struct address_space *mapping,
1852                         loff_t pos, unsigned len, unsigned copied,
1853                         struct page *page, void *fsdata)
1854 {
1855         struct inode *inode = page->mapping->host;
1856
1857         trace_f2fs_write_end(inode, pos, len, copied);
1858
1859         /*
1860          * This should be come from len == PAGE_SIZE, and we expect copied
1861          * should be PAGE_SIZE. Otherwise, we treat it with zero copied and
1862          * let generic_perform_write() try to copy data again through copied=0.
1863          */
1864         if (!PageUptodate(page)) {
1865                 if (unlikely(copied != len))
1866                         copied = 0;
1867                 else
1868                         SetPageUptodate(page);
1869         }
1870         if (!copied)
1871                 goto unlock_out;
1872
1873         set_page_dirty(page);
1874
1875         if (pos + copied > i_size_read(inode))
1876                 f2fs_i_size_write(inode, pos + copied);
1877 unlock_out:
1878         f2fs_put_page(page, 1);
1879         f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
1880         return copied;
1881 }
1882
1883 static int check_direct_IO(struct inode *inode, struct iov_iter *iter,
1884                            loff_t offset)
1885 {
1886         unsigned blocksize_mask = inode->i_sb->s_blocksize - 1;
1887
1888         if (offset & blocksize_mask)
1889                 return -EINVAL;
1890
1891         if (iov_iter_alignment(iter) & blocksize_mask)
1892                 return -EINVAL;
1893
1894         return 0;
1895 }
1896
1897 static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
1898 {
1899         struct address_space *mapping = iocb->ki_filp->f_mapping;
1900         struct inode *inode = mapping->host;
1901         size_t count = iov_iter_count(iter);
1902         loff_t offset = iocb->ki_pos;
1903         int rw = iov_iter_rw(iter);
1904         int err;
1905
1906         err = check_direct_IO(inode, iter, offset);
1907         if (err)
1908                 return err;
1909
1910         if (__force_buffered_io(inode, rw))
1911                 return 0;
1912
1913         trace_f2fs_direct_IO_enter(inode, offset, count, rw);
1914
1915         down_read(&F2FS_I(inode)->dio_rwsem[rw]);
1916         err = blockdev_direct_IO(iocb, inode, iter, get_data_block_dio);
1917         up_read(&F2FS_I(inode)->dio_rwsem[rw]);
1918
1919         if (rw == WRITE) {
1920                 if (err > 0)
1921                         set_inode_flag(inode, FI_UPDATE_WRITE);
1922                 else if (err < 0)
1923                         f2fs_write_failed(mapping, offset + count);
1924         }
1925
1926         trace_f2fs_direct_IO_exit(inode, offset, count, rw, err);
1927
1928         return err;
1929 }
1930
1931 void f2fs_invalidate_page(struct page *page, unsigned int offset,
1932                                                         unsigned int length)
1933 {
1934         struct inode *inode = page->mapping->host;
1935         struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1936
1937         if (inode->i_ino >= F2FS_ROOT_INO(sbi) &&
1938                 (offset % PAGE_SIZE || length != PAGE_SIZE))
1939                 return;
1940
1941         if (PageDirty(page)) {
1942                 if (inode->i_ino == F2FS_META_INO(sbi)) {
1943                         dec_page_count(sbi, F2FS_DIRTY_META);
1944                 } else if (inode->i_ino == F2FS_NODE_INO(sbi)) {
1945                         dec_page_count(sbi, F2FS_DIRTY_NODES);
1946                 } else {
1947                         inode_dec_dirty_pages(inode);
1948                         remove_dirty_inode(inode);
1949                 }
1950         }
1951
1952         /* This is atomic written page, keep Private */
1953         if (IS_ATOMIC_WRITTEN_PAGE(page))
1954                 return;
1955
1956         set_page_private(page, 0);
1957         ClearPagePrivate(page);
1958 }
1959
1960 int f2fs_release_page(struct page *page, gfp_t wait)
1961 {
1962         /* If this is dirty page, keep PagePrivate */
1963         if (PageDirty(page))
1964                 return 0;
1965
1966         /* This is atomic written page, keep Private */
1967         if (IS_ATOMIC_WRITTEN_PAGE(page))
1968                 return 0;
1969
1970         set_page_private(page, 0);
1971         ClearPagePrivate(page);
1972         return 1;
1973 }
1974
1975 /*
1976  * This was copied from __set_page_dirty_buffers which gives higher performance
1977  * in very high speed storages. (e.g., pmem)
1978  */
1979 void f2fs_set_page_dirty_nobuffers(struct page *page)
1980 {
1981         struct address_space *mapping = page->mapping;
1982         unsigned long flags;
1983
1984         if (unlikely(!mapping))
1985                 return;
1986
1987         spin_lock(&mapping->private_lock);
1988         lock_page_memcg(page);
1989         SetPageDirty(page);
1990         spin_unlock(&mapping->private_lock);
1991
1992         spin_lock_irqsave(&mapping->tree_lock, flags);
1993         WARN_ON_ONCE(!PageUptodate(page));
1994         account_page_dirtied(page, mapping);
1995         radix_tree_tag_set(&mapping->page_tree,
1996                         page_index(page), PAGECACHE_TAG_DIRTY);
1997         spin_unlock_irqrestore(&mapping->tree_lock, flags);
1998         unlock_page_memcg(page);
1999
2000         __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
2001         return;
2002 }
2003
2004 static int f2fs_set_data_page_dirty(struct page *page)
2005 {
2006         struct address_space *mapping = page->mapping;
2007         struct inode *inode = mapping->host;
2008
2009         trace_f2fs_set_page_dirty(page, DATA);
2010
2011         if (!PageUptodate(page))
2012                 SetPageUptodate(page);
2013
2014         if (f2fs_is_atomic_file(inode) && !f2fs_is_commit_atomic_write(inode)) {
2015                 if (!IS_ATOMIC_WRITTEN_PAGE(page)) {
2016                         register_inmem_page(inode, page);
2017                         return 1;
2018                 }
2019                 /*
2020                  * Previously, this page has been registered, we just
2021                  * return here.
2022                  */
2023                 return 0;
2024         }
2025
2026         if (!PageDirty(page)) {
2027                 f2fs_set_page_dirty_nobuffers(page);
2028                 update_dirty_page(inode, page);
2029                 return 1;
2030         }
2031         return 0;
2032 }
2033
2034 static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
2035 {
2036         struct inode *inode = mapping->host;
2037
2038         if (f2fs_has_inline_data(inode))
2039                 return 0;
2040
2041         /* make sure allocating whole blocks */
2042         if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
2043                 filemap_write_and_wait(mapping);
2044
2045         return generic_block_bmap(mapping, block, get_data_block_bmap);
2046 }
2047
2048 #ifdef CONFIG_MIGRATION
2049 #include <linux/migrate.h>
2050
2051 int f2fs_migrate_page(struct address_space *mapping,
2052                 struct page *newpage, struct page *page, enum migrate_mode mode)
2053 {
2054         int rc, extra_count;
2055         struct f2fs_inode_info *fi = F2FS_I(mapping->host);
2056         bool atomic_written = IS_ATOMIC_WRITTEN_PAGE(page);
2057
2058         BUG_ON(PageWriteback(page));
2059
2060         /* migrating an atomic written page is safe with the inmem_lock hold */
2061         if (atomic_written && !mutex_trylock(&fi->inmem_lock))
2062                 return -EAGAIN;
2063
2064         /*
2065          * A reference is expected if PagePrivate set when move mapping,
2066          * however F2FS breaks this for maintaining dirty page counts when
2067          * truncating pages. So here adjusting the 'extra_count' make it work.
2068          */
2069         extra_count = (atomic_written ? 1 : 0) - page_has_private(page);
2070         rc = migrate_page_move_mapping(mapping, newpage,
2071                                 page, NULL, mode, extra_count);
2072         if (rc != MIGRATEPAGE_SUCCESS) {
2073                 if (atomic_written)
2074                         mutex_unlock(&fi->inmem_lock);
2075                 return rc;
2076         }
2077
2078         if (atomic_written) {
2079                 struct inmem_pages *cur;
2080                 list_for_each_entry(cur, &fi->inmem_pages, list)
2081                         if (cur->page == page) {
2082                                 cur->page = newpage;
2083                                 break;
2084                         }
2085                 mutex_unlock(&fi->inmem_lock);
2086                 put_page(page);
2087                 get_page(newpage);
2088         }
2089
2090         if (PagePrivate(page))
2091                 SetPagePrivate(newpage);
2092         set_page_private(newpage, page_private(page));
2093
2094         migrate_page_copy(newpage, page);
2095
2096         return MIGRATEPAGE_SUCCESS;
2097 }
2098 #endif
2099
2100 const struct address_space_operations f2fs_dblock_aops = {
2101         .readpage       = f2fs_read_data_page,
2102         .readpages      = f2fs_read_data_pages,
2103         .writepage      = f2fs_write_data_page,
2104         .writepages     = f2fs_write_data_pages,
2105         .write_begin    = f2fs_write_begin,
2106         .write_end      = f2fs_write_end,
2107         .set_page_dirty = f2fs_set_data_page_dirty,
2108         .invalidatepage = f2fs_invalidate_page,
2109         .releasepage    = f2fs_release_page,
2110         .direct_IO      = f2fs_direct_IO,
2111         .bmap           = f2fs_bmap,
2112 #ifdef CONFIG_MIGRATION
2113         .migratepage    = f2fs_migrate_page,
2114 #endif
2115 };