linux/fs/f2fs/data.c
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   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
  33static 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
  53static 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_first_page_all(bio)), FAULT_IO)) {
  60                f2fs_show_injection_info(FAULT_IO);
  61                bio->bi_status = BLK_STS_IOERR;
  62        }
  63#endif
  64
  65        if (f2fs_bio_encrypted(bio)) {
  66                if (bio->bi_status) {
  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_status) {
  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
  89static 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_status))
 106                                f2fs_stop_checkpoint(sbi, true);
 107                        continue;
 108                }
 109
 110                fscrypt_pullback_bio_page(&page, true);
 111
 112                if (unlikely(bio->bi_status)) {
 113                        mapping_set_error(page->mapping, -EIO);
 114                        if (type == F2FS_WB_CP_DATA)
 115                                f2fs_stop_checkpoint(sbi, true);
 116                }
 117
 118                f2fs_bug_on(sbi, page->mapping == NODE_MAPPING(sbi) &&
 119                                        page->index != nid_of_node(page));
 120
 121                dec_page_count(sbi, type);
 122                clear_cold_data(page);
 123                end_page_writeback(page);
 124        }
 125        if (!get_pages(sbi, F2FS_WB_CP_DATA) &&
 126                                wq_has_sleeper(&sbi->cp_wait))
 127                wake_up(&sbi->cp_wait);
 128
 129        bio_put(bio);
 130}
 131
 132/*
 133 * Return true, if pre_bio's bdev is same as its target device.
 134 */
 135struct block_device *f2fs_target_device(struct f2fs_sb_info *sbi,
 136                                block_t blk_addr, struct bio *bio)
 137{
 138        struct block_device *bdev = sbi->sb->s_bdev;
 139        int i;
 140
 141        for (i = 0; i < sbi->s_ndevs; i++) {
 142                if (FDEV(i).start_blk <= blk_addr &&
 143                                        FDEV(i).end_blk >= blk_addr) {
 144                        blk_addr -= FDEV(i).start_blk;
 145                        bdev = FDEV(i).bdev;
 146                        break;
 147                }
 148        }
 149        if (bio) {
 150                bio_set_dev(bio, bdev);
 151                bio->bi_iter.bi_sector = SECTOR_FROM_BLOCK(blk_addr);
 152        }
 153        return bdev;
 154}
 155
 156int f2fs_target_device_index(struct f2fs_sb_info *sbi, block_t blkaddr)
 157{
 158        int i;
 159
 160        for (i = 0; i < sbi->s_ndevs; i++)
 161                if (FDEV(i).start_blk <= blkaddr && FDEV(i).end_blk >= blkaddr)
 162                        return i;
 163        return 0;
 164}
 165
 166static bool __same_bdev(struct f2fs_sb_info *sbi,
 167                                block_t blk_addr, struct bio *bio)
 168{
 169        struct block_device *b = f2fs_target_device(sbi, blk_addr, NULL);
 170        return bio->bi_disk == b->bd_disk && bio->bi_partno == b->bd_partno;
 171}
 172
 173/*
 174 * Low-level block read/write IO operations.
 175 */
 176static struct bio *__bio_alloc(struct f2fs_sb_info *sbi, block_t blk_addr,
 177                                struct writeback_control *wbc,
 178                                int npages, bool is_read,
 179                                enum page_type type, enum temp_type temp)
 180{
 181        struct bio *bio;
 182
 183        bio = f2fs_bio_alloc(sbi, npages, true);
 184
 185        f2fs_target_device(sbi, blk_addr, bio);
 186        if (is_read) {
 187                bio->bi_end_io = f2fs_read_end_io;
 188                bio->bi_private = NULL;
 189        } else {
 190                bio->bi_end_io = f2fs_write_end_io;
 191                bio->bi_private = sbi;
 192                bio->bi_write_hint = io_type_to_rw_hint(sbi, type, temp);
 193        }
 194        if (wbc)
 195                wbc_init_bio(wbc, bio);
 196
 197        return bio;
 198}
 199
 200static inline void __submit_bio(struct f2fs_sb_info *sbi,
 201                                struct bio *bio, enum page_type type)
 202{
 203        if (!is_read_io(bio_op(bio))) {
 204                unsigned int start;
 205
 206                if (type != DATA && type != NODE)
 207                        goto submit_io;
 208
 209                if (f2fs_sb_has_blkzoned(sbi->sb) && current->plug)
 210                        blk_finish_plug(current->plug);
 211
 212                start = bio->bi_iter.bi_size >> F2FS_BLKSIZE_BITS;
 213                start %= F2FS_IO_SIZE(sbi);
 214
 215                if (start == 0)
 216                        goto submit_io;
 217
 218                /* fill dummy pages */
 219                for (; start < F2FS_IO_SIZE(sbi); start++) {
 220                        struct page *page =
 221                                mempool_alloc(sbi->write_io_dummy,
 222                                        GFP_NOIO | __GFP_ZERO | __GFP_NOFAIL);
 223                        f2fs_bug_on(sbi, !page);
 224
 225                        SetPagePrivate(page);
 226                        set_page_private(page, (unsigned long)DUMMY_WRITTEN_PAGE);
 227                        lock_page(page);
 228                        if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE)
 229                                f2fs_bug_on(sbi, 1);
 230                }
 231                /*
 232                 * In the NODE case, we lose next block address chain. So, we
 233                 * need to do checkpoint in f2fs_sync_file.
 234                 */
 235                if (type == NODE)
 236                        set_sbi_flag(sbi, SBI_NEED_CP);
 237        }
 238submit_io:
 239        if (is_read_io(bio_op(bio)))
 240                trace_f2fs_submit_read_bio(sbi->sb, type, bio);
 241        else
 242                trace_f2fs_submit_write_bio(sbi->sb, type, bio);
 243        submit_bio(bio);
 244}
 245
 246static void __submit_merged_bio(struct f2fs_bio_info *io)
 247{
 248        struct f2fs_io_info *fio = &io->fio;
 249
 250        if (!io->bio)
 251                return;
 252
 253        bio_set_op_attrs(io->bio, fio->op, fio->op_flags);
 254
 255        if (is_read_io(fio->op))
 256                trace_f2fs_prepare_read_bio(io->sbi->sb, fio->type, io->bio);
 257        else
 258                trace_f2fs_prepare_write_bio(io->sbi->sb, fio->type, io->bio);
 259
 260        __submit_bio(io->sbi, io->bio, fio->type);
 261        io->bio = NULL;
 262}
 263
 264static bool __has_merged_page(struct f2fs_bio_info *io,
 265                                struct inode *inode, nid_t ino, pgoff_t idx)
 266{
 267        struct bio_vec *bvec;
 268        struct page *target;
 269        int i;
 270
 271        if (!io->bio)
 272                return false;
 273
 274        if (!inode && !ino)
 275                return true;
 276
 277        bio_for_each_segment_all(bvec, io->bio, i) {
 278
 279                if (bvec->bv_page->mapping)
 280                        target = bvec->bv_page;
 281                else
 282                        target = fscrypt_control_page(bvec->bv_page);
 283
 284                if (idx != target->index)
 285                        continue;
 286
 287                if (inode && inode == target->mapping->host)
 288                        return true;
 289                if (ino && ino == ino_of_node(target))
 290                        return true;
 291        }
 292
 293        return false;
 294}
 295
 296static bool has_merged_page(struct f2fs_sb_info *sbi, struct inode *inode,
 297                                nid_t ino, pgoff_t idx, enum page_type type)
 298{
 299        enum page_type btype = PAGE_TYPE_OF_BIO(type);
 300        enum temp_type temp;
 301        struct f2fs_bio_info *io;
 302        bool ret = false;
 303
 304        for (temp = HOT; temp < NR_TEMP_TYPE; temp++) {
 305                io = sbi->write_io[btype] + temp;
 306
 307                down_read(&io->io_rwsem);
 308                ret = __has_merged_page(io, inode, ino, idx);
 309                up_read(&io->io_rwsem);
 310
 311                /* TODO: use HOT temp only for meta pages now. */
 312                if (ret || btype == META)
 313                        break;
 314        }
 315        return ret;
 316}
 317
 318static void __f2fs_submit_merged_write(struct f2fs_sb_info *sbi,
 319                                enum page_type type, enum temp_type temp)
 320{
 321        enum page_type btype = PAGE_TYPE_OF_BIO(type);
 322        struct f2fs_bio_info *io = sbi->write_io[btype] + temp;
 323
 324        down_write(&io->io_rwsem);
 325
 326        /* change META to META_FLUSH in the checkpoint procedure */
 327        if (type >= META_FLUSH) {
 328                io->fio.type = META_FLUSH;
 329                io->fio.op = REQ_OP_WRITE;
 330                io->fio.op_flags = REQ_META | REQ_PRIO | REQ_SYNC;
 331                if (!test_opt(sbi, NOBARRIER))
 332                        io->fio.op_flags |= REQ_PREFLUSH | REQ_FUA;
 333        }
 334        __submit_merged_bio(io);
 335        up_write(&io->io_rwsem);
 336}
 337
 338static void __submit_merged_write_cond(struct f2fs_sb_info *sbi,
 339                                struct inode *inode, nid_t ino, pgoff_t idx,
 340                                enum page_type type, bool force)
 341{
 342        enum temp_type temp;
 343
 344        if (!force && !has_merged_page(sbi, inode, ino, idx, type))
 345                return;
 346
 347        for (temp = HOT; temp < NR_TEMP_TYPE; temp++) {
 348
 349                __f2fs_submit_merged_write(sbi, type, temp);
 350
 351                /* TODO: use HOT temp only for meta pages now. */
 352                if (type >= META)
 353                        break;
 354        }
 355}
 356
 357void f2fs_submit_merged_write(struct f2fs_sb_info *sbi, enum page_type type)
 358{
 359        __submit_merged_write_cond(sbi, NULL, 0, 0, type, true);
 360}
 361
 362void f2fs_submit_merged_write_cond(struct f2fs_sb_info *sbi,
 363                                struct inode *inode, nid_t ino, pgoff_t idx,
 364                                enum page_type type)
 365{
 366        __submit_merged_write_cond(sbi, inode, ino, idx, type, false);
 367}
 368
 369void f2fs_flush_merged_writes(struct f2fs_sb_info *sbi)
 370{
 371        f2fs_submit_merged_write(sbi, DATA);
 372        f2fs_submit_merged_write(sbi, NODE);
 373        f2fs_submit_merged_write(sbi, META);
 374}
 375
 376/*
 377 * Fill the locked page with data located in the block address.
 378 * A caller needs to unlock the page on failure.
 379 */
 380int f2fs_submit_page_bio(struct f2fs_io_info *fio)
 381{
 382        struct bio *bio;
 383        struct page *page = fio->encrypted_page ?
 384                        fio->encrypted_page : fio->page;
 385
 386        verify_block_addr(fio, fio->new_blkaddr);
 387        trace_f2fs_submit_page_bio(page, fio);
 388        f2fs_trace_ios(fio, 0);
 389
 390        /* Allocate a new bio */
 391        bio = __bio_alloc(fio->sbi, fio->new_blkaddr, fio->io_wbc,
 392                                1, is_read_io(fio->op), fio->type, fio->temp);
 393
 394        if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
 395                bio_put(bio);
 396                return -EFAULT;
 397        }
 398        bio_set_op_attrs(bio, fio->op, fio->op_flags);
 399
 400        __submit_bio(fio->sbi, bio, fio->type);
 401
 402        if (!is_read_io(fio->op))
 403                inc_page_count(fio->sbi, WB_DATA_TYPE(fio->page));
 404        return 0;
 405}
 406
 407int f2fs_submit_page_write(struct f2fs_io_info *fio)
 408{
 409        struct f2fs_sb_info *sbi = fio->sbi;
 410        enum page_type btype = PAGE_TYPE_OF_BIO(fio->type);
 411        struct f2fs_bio_info *io = sbi->write_io[btype] + fio->temp;
 412        struct page *bio_page;
 413        int err = 0;
 414
 415        f2fs_bug_on(sbi, is_read_io(fio->op));
 416
 417        down_write(&io->io_rwsem);
 418next:
 419        if (fio->in_list) {
 420                spin_lock(&io->io_lock);
 421                if (list_empty(&io->io_list)) {
 422                        spin_unlock(&io->io_lock);
 423                        goto out_fail;
 424                }
 425                fio = list_first_entry(&io->io_list,
 426                                                struct f2fs_io_info, list);
 427                list_del(&fio->list);
 428                spin_unlock(&io->io_lock);
 429        }
 430
 431        if (fio->old_blkaddr != NEW_ADDR)
 432                verify_block_addr(fio, fio->old_blkaddr);
 433        verify_block_addr(fio, fio->new_blkaddr);
 434
 435        bio_page = fio->encrypted_page ? fio->encrypted_page : fio->page;
 436
 437        /* set submitted = true as a return value */
 438        fio->submitted = true;
 439
 440        inc_page_count(sbi, WB_DATA_TYPE(bio_page));
 441
 442        if (io->bio && (io->last_block_in_bio != fio->new_blkaddr - 1 ||
 443            (io->fio.op != fio->op || io->fio.op_flags != fio->op_flags) ||
 444                        !__same_bdev(sbi, fio->new_blkaddr, io->bio)))
 445                __submit_merged_bio(io);
 446alloc_new:
 447        if (io->bio == NULL) {
 448                if ((fio->type == DATA || fio->type == NODE) &&
 449                                fio->new_blkaddr & F2FS_IO_SIZE_MASK(sbi)) {
 450                        err = -EAGAIN;
 451                        dec_page_count(sbi, WB_DATA_TYPE(bio_page));
 452                        goto out_fail;
 453                }
 454                io->bio = __bio_alloc(sbi, fio->new_blkaddr, fio->io_wbc,
 455                                                BIO_MAX_PAGES, false,
 456                                                fio->type, fio->temp);
 457                io->fio = *fio;
 458        }
 459
 460        if (bio_add_page(io->bio, bio_page, PAGE_SIZE, 0) < PAGE_SIZE) {
 461                __submit_merged_bio(io);
 462                goto alloc_new;
 463        }
 464
 465        if (fio->io_wbc)
 466                wbc_account_io(fio->io_wbc, bio_page, PAGE_SIZE);
 467
 468        io->last_block_in_bio = fio->new_blkaddr;
 469        f2fs_trace_ios(fio, 0);
 470
 471        trace_f2fs_submit_page_write(fio->page, fio);
 472
 473        if (fio->in_list)
 474                goto next;
 475out_fail:
 476        up_write(&io->io_rwsem);
 477        return err;
 478}
 479
 480static struct bio *f2fs_grab_read_bio(struct inode *inode, block_t blkaddr,
 481                                                         unsigned nr_pages)
 482{
 483        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 484        struct fscrypt_ctx *ctx = NULL;
 485        struct bio *bio;
 486
 487        if (f2fs_encrypted_file(inode)) {
 488                ctx = fscrypt_get_ctx(inode, GFP_NOFS);
 489                if (IS_ERR(ctx))
 490                        return ERR_CAST(ctx);
 491
 492                /* wait the page to be moved by cleaning */
 493                f2fs_wait_on_block_writeback(sbi, blkaddr);
 494        }
 495
 496        bio = f2fs_bio_alloc(sbi, min_t(int, nr_pages, BIO_MAX_PAGES), false);
 497        if (!bio) {
 498                if (ctx)
 499                        fscrypt_release_ctx(ctx);
 500                return ERR_PTR(-ENOMEM);
 501        }
 502        f2fs_target_device(sbi, blkaddr, bio);
 503        bio->bi_end_io = f2fs_read_end_io;
 504        bio->bi_private = ctx;
 505        bio_set_op_attrs(bio, REQ_OP_READ, 0);
 506
 507        return bio;
 508}
 509
 510/* This can handle encryption stuffs */
 511static int f2fs_submit_page_read(struct inode *inode, struct page *page,
 512                                                        block_t blkaddr)
 513{
 514        struct bio *bio = f2fs_grab_read_bio(inode, blkaddr, 1);
 515
 516        if (IS_ERR(bio))
 517                return PTR_ERR(bio);
 518
 519        if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
 520                bio_put(bio);
 521                return -EFAULT;
 522        }
 523        __submit_bio(F2FS_I_SB(inode), bio, DATA);
 524        return 0;
 525}
 526
 527static void __set_data_blkaddr(struct dnode_of_data *dn)
 528{
 529        struct f2fs_node *rn = F2FS_NODE(dn->node_page);
 530        __le32 *addr_array;
 531        int base = 0;
 532
 533        if (IS_INODE(dn->node_page) && f2fs_has_extra_attr(dn->inode))
 534                base = get_extra_isize(dn->inode);
 535
 536        /* Get physical address of data block */
 537        addr_array = blkaddr_in_node(rn);
 538        addr_array[base + dn->ofs_in_node] = cpu_to_le32(dn->data_blkaddr);
 539}
 540
 541/*
 542 * Lock ordering for the change of data block address:
 543 * ->data_page
 544 *  ->node_page
 545 *    update block addresses in the node page
 546 */
 547void set_data_blkaddr(struct dnode_of_data *dn)
 548{
 549        f2fs_wait_on_page_writeback(dn->node_page, NODE, true);
 550        __set_data_blkaddr(dn);
 551        if (set_page_dirty(dn->node_page))
 552                dn->node_changed = true;
 553}
 554
 555void f2fs_update_data_blkaddr(struct dnode_of_data *dn, block_t blkaddr)
 556{
 557        dn->data_blkaddr = blkaddr;
 558        set_data_blkaddr(dn);
 559        f2fs_update_extent_cache(dn);
 560}
 561
 562/* dn->ofs_in_node will be returned with up-to-date last block pointer */
 563int reserve_new_blocks(struct dnode_of_data *dn, blkcnt_t count)
 564{
 565        struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
 566        int err;
 567
 568        if (!count)
 569                return 0;
 570
 571        if (unlikely(is_inode_flag_set(dn->inode, FI_NO_ALLOC)))
 572                return -EPERM;
 573        if (unlikely((err = inc_valid_block_count(sbi, dn->inode, &count))))
 574                return err;
 575
 576        trace_f2fs_reserve_new_blocks(dn->inode, dn->nid,
 577                                                dn->ofs_in_node, count);
 578
 579        f2fs_wait_on_page_writeback(dn->node_page, NODE, true);
 580
 581        for (; count > 0; dn->ofs_in_node++) {
 582                block_t blkaddr = datablock_addr(dn->inode,
 583                                        dn->node_page, dn->ofs_in_node);
 584                if (blkaddr == NULL_ADDR) {
 585                        dn->data_blkaddr = NEW_ADDR;
 586                        __set_data_blkaddr(dn);
 587                        count--;
 588                }
 589        }
 590
 591        if (set_page_dirty(dn->node_page))
 592                dn->node_changed = true;
 593        return 0;
 594}
 595
 596/* Should keep dn->ofs_in_node unchanged */
 597int reserve_new_block(struct dnode_of_data *dn)
 598{
 599        unsigned int ofs_in_node = dn->ofs_in_node;
 600        int ret;
 601
 602        ret = reserve_new_blocks(dn, 1);
 603        dn->ofs_in_node = ofs_in_node;
 604        return ret;
 605}
 606
 607int f2fs_reserve_block(struct dnode_of_data *dn, pgoff_t index)
 608{
 609        bool need_put = dn->inode_page ? false : true;
 610        int err;
 611
 612        err = get_dnode_of_data(dn, index, ALLOC_NODE);
 613        if (err)
 614                return err;
 615
 616        if (dn->data_blkaddr == NULL_ADDR)
 617                err = reserve_new_block(dn);
 618        if (err || need_put)
 619                f2fs_put_dnode(dn);
 620        return err;
 621}
 622
 623int f2fs_get_block(struct dnode_of_data *dn, pgoff_t index)
 624{
 625        struct extent_info ei  = {0,0,0};
 626        struct inode *inode = dn->inode;
 627
 628        if (f2fs_lookup_extent_cache(inode, index, &ei)) {
 629                dn->data_blkaddr = ei.blk + index - ei.fofs;
 630                return 0;
 631        }
 632
 633        return f2fs_reserve_block(dn, index);
 634}
 635
 636struct page *get_read_data_page(struct inode *inode, pgoff_t index,
 637                                                int op_flags, bool for_write)
 638{
 639        struct address_space *mapping = inode->i_mapping;
 640        struct dnode_of_data dn;
 641        struct page *page;
 642        struct extent_info ei = {0,0,0};
 643        int err;
 644
 645        page = f2fs_grab_cache_page(mapping, index, for_write);
 646        if (!page)
 647                return ERR_PTR(-ENOMEM);
 648
 649        if (f2fs_lookup_extent_cache(inode, index, &ei)) {
 650                dn.data_blkaddr = ei.blk + index - ei.fofs;
 651                goto got_it;
 652        }
 653
 654        set_new_dnode(&dn, inode, NULL, NULL, 0);
 655        err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
 656        if (err)
 657                goto put_err;
 658        f2fs_put_dnode(&dn);
 659
 660        if (unlikely(dn.data_blkaddr == NULL_ADDR)) {
 661                err = -ENOENT;
 662                goto put_err;
 663        }
 664got_it:
 665        if (PageUptodate(page)) {
 666                unlock_page(page);
 667                return page;
 668        }
 669
 670        /*
 671         * A new dentry page is allocated but not able to be written, since its
 672         * new inode page couldn't be allocated due to -ENOSPC.
 673         * In such the case, its blkaddr can be remained as NEW_ADDR.
 674         * see, f2fs_add_link -> get_new_data_page -> init_inode_metadata.
 675         */
 676        if (dn.data_blkaddr == NEW_ADDR) {
 677                zero_user_segment(page, 0, PAGE_SIZE);
 678                if (!PageUptodate(page))
 679                        SetPageUptodate(page);
 680                unlock_page(page);
 681                return page;
 682        }
 683
 684        err = f2fs_submit_page_read(inode, page, dn.data_blkaddr);
 685        if (err)
 686                goto put_err;
 687        return page;
 688
 689put_err:
 690        f2fs_put_page(page, 1);
 691        return ERR_PTR(err);
 692}
 693
 694struct page *find_data_page(struct inode *inode, pgoff_t index)
 695{
 696        struct address_space *mapping = inode->i_mapping;
 697        struct page *page;
 698
 699        page = find_get_page(mapping, index);
 700        if (page && PageUptodate(page))
 701                return page;
 702        f2fs_put_page(page, 0);
 703
 704        page = get_read_data_page(inode, index, 0, false);
 705        if (IS_ERR(page))
 706                return page;
 707
 708        if (PageUptodate(page))
 709                return page;
 710
 711        wait_on_page_locked(page);
 712        if (unlikely(!PageUptodate(page))) {
 713                f2fs_put_page(page, 0);
 714                return ERR_PTR(-EIO);
 715        }
 716        return page;
 717}
 718
 719/*
 720 * If it tries to access a hole, return an error.
 721 * Because, the callers, functions in dir.c and GC, should be able to know
 722 * whether this page exists or not.
 723 */
 724struct page *get_lock_data_page(struct inode *inode, pgoff_t index,
 725                                                        bool for_write)
 726{
 727        struct address_space *mapping = inode->i_mapping;
 728        struct page *page;
 729repeat:
 730        page = get_read_data_page(inode, index, 0, for_write);
 731        if (IS_ERR(page))
 732                return page;
 733
 734        /* wait for read completion */
 735        lock_page(page);
 736        if (unlikely(page->mapping != mapping)) {
 737                f2fs_put_page(page, 1);
 738                goto repeat;
 739        }
 740        if (unlikely(!PageUptodate(page))) {
 741                f2fs_put_page(page, 1);
 742                return ERR_PTR(-EIO);
 743        }
 744        return page;
 745}
 746
 747/*
 748 * Caller ensures that this data page is never allocated.
 749 * A new zero-filled data page is allocated in the page cache.
 750 *
 751 * Also, caller should grab and release a rwsem by calling f2fs_lock_op() and
 752 * f2fs_unlock_op().
 753 * Note that, ipage is set only by make_empty_dir, and if any error occur,
 754 * ipage should be released by this function.
 755 */
 756struct page *get_new_data_page(struct inode *inode,
 757                struct page *ipage, pgoff_t index, bool new_i_size)
 758{
 759        struct address_space *mapping = inode->i_mapping;
 760        struct page *page;
 761        struct dnode_of_data dn;
 762        int err;
 763
 764        page = f2fs_grab_cache_page(mapping, index, true);
 765        if (!page) {
 766                /*
 767                 * before exiting, we should make sure ipage will be released
 768                 * if any error occur.
 769                 */
 770                f2fs_put_page(ipage, 1);
 771                return ERR_PTR(-ENOMEM);
 772        }
 773
 774        set_new_dnode(&dn, inode, ipage, NULL, 0);
 775        err = f2fs_reserve_block(&dn, index);
 776        if (err) {
 777                f2fs_put_page(page, 1);
 778                return ERR_PTR(err);
 779        }
 780        if (!ipage)
 781                f2fs_put_dnode(&dn);
 782
 783        if (PageUptodate(page))
 784                goto got_it;
 785
 786        if (dn.data_blkaddr == NEW_ADDR) {
 787                zero_user_segment(page, 0, PAGE_SIZE);
 788                if (!PageUptodate(page))
 789                        SetPageUptodate(page);
 790        } else {
 791                f2fs_put_page(page, 1);
 792
 793                /* if ipage exists, blkaddr should be NEW_ADDR */
 794                f2fs_bug_on(F2FS_I_SB(inode), ipage);
 795                page = get_lock_data_page(inode, index, true);
 796                if (IS_ERR(page))
 797                        return page;
 798        }
 799got_it:
 800        if (new_i_size && i_size_read(inode) <
 801                                ((loff_t)(index + 1) << PAGE_SHIFT))
 802                f2fs_i_size_write(inode, ((loff_t)(index + 1) << PAGE_SHIFT));
 803        return page;
 804}
 805
 806static int __allocate_data_block(struct dnode_of_data *dn, int seg_type)
 807{
 808        struct f2fs_sb_info *sbi = F2FS_I_SB(dn->inode);
 809        struct f2fs_summary sum;
 810        struct node_info ni;
 811        pgoff_t fofs;
 812        blkcnt_t count = 1;
 813        int err;
 814
 815        if (unlikely(is_inode_flag_set(dn->inode, FI_NO_ALLOC)))
 816                return -EPERM;
 817
 818        dn->data_blkaddr = datablock_addr(dn->inode,
 819                                dn->node_page, dn->ofs_in_node);
 820        if (dn->data_blkaddr == NEW_ADDR)
 821                goto alloc;
 822
 823        if (unlikely((err = inc_valid_block_count(sbi, dn->inode, &count))))
 824                return err;
 825
 826alloc:
 827        get_node_info(sbi, dn->nid, &ni);
 828        set_summary(&sum, dn->nid, dn->ofs_in_node, ni.version);
 829
 830        allocate_data_block(sbi, NULL, dn->data_blkaddr, &dn->data_blkaddr,
 831                                        &sum, seg_type, NULL, false);
 832        set_data_blkaddr(dn);
 833
 834        /* update i_size */
 835        fofs = start_bidx_of_node(ofs_of_node(dn->node_page), dn->inode) +
 836                                                        dn->ofs_in_node;
 837        if (i_size_read(dn->inode) < ((loff_t)(fofs + 1) << PAGE_SHIFT))
 838                f2fs_i_size_write(dn->inode,
 839                                ((loff_t)(fofs + 1) << PAGE_SHIFT));
 840        return 0;
 841}
 842
 843int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from)
 844{
 845        struct inode *inode = file_inode(iocb->ki_filp);
 846        struct f2fs_map_blocks map;
 847        int flag;
 848        int err = 0;
 849        bool direct_io = iocb->ki_flags & IOCB_DIRECT;
 850
 851        /* convert inline data for Direct I/O*/
 852        if (direct_io) {
 853                err = f2fs_convert_inline_inode(inode);
 854                if (err)
 855                        return err;
 856        }
 857
 858        if (is_inode_flag_set(inode, FI_NO_PREALLOC))
 859                return 0;
 860
 861        map.m_lblk = F2FS_BLK_ALIGN(iocb->ki_pos);
 862        map.m_len = F2FS_BYTES_TO_BLK(iocb->ki_pos + iov_iter_count(from));
 863        if (map.m_len > map.m_lblk)
 864                map.m_len -= map.m_lblk;
 865        else
 866                map.m_len = 0;
 867
 868        map.m_next_pgofs = NULL;
 869        map.m_next_extent = NULL;
 870        map.m_seg_type = NO_CHECK_TYPE;
 871
 872        if (direct_io) {
 873                map.m_seg_type = rw_hint_to_seg_type(iocb->ki_hint);
 874                flag = f2fs_force_buffered_io(inode, WRITE) ?
 875                                        F2FS_GET_BLOCK_PRE_AIO :
 876                                        F2FS_GET_BLOCK_PRE_DIO;
 877                goto map_blocks;
 878        }
 879        if (iocb->ki_pos + iov_iter_count(from) > MAX_INLINE_DATA(inode)) {
 880                err = f2fs_convert_inline_inode(inode);
 881                if (err)
 882                        return err;
 883        }
 884        if (f2fs_has_inline_data(inode))
 885                return err;
 886
 887        flag = F2FS_GET_BLOCK_PRE_AIO;
 888
 889map_blocks:
 890        err = f2fs_map_blocks(inode, &map, 1, flag);
 891        if (map.m_len > 0 && err == -ENOSPC) {
 892                if (!direct_io)
 893                        set_inode_flag(inode, FI_NO_PREALLOC);
 894                err = 0;
 895        }
 896        return err;
 897}
 898
 899static inline void __do_map_lock(struct f2fs_sb_info *sbi, int flag, bool lock)
 900{
 901        if (flag == F2FS_GET_BLOCK_PRE_AIO) {
 902                if (lock)
 903                        down_read(&sbi->node_change);
 904                else
 905                        up_read(&sbi->node_change);
 906        } else {
 907                if (lock)
 908                        f2fs_lock_op(sbi);
 909                else
 910                        f2fs_unlock_op(sbi);
 911        }
 912}
 913
 914/*
 915 * f2fs_map_blocks() now supported readahead/bmap/rw direct_IO with
 916 * f2fs_map_blocks structure.
 917 * If original data blocks are allocated, then give them to blockdev.
 918 * Otherwise,
 919 *     a. preallocate requested block addresses
 920 *     b. do not use extent cache for better performance
 921 *     c. give the block addresses to blockdev
 922 */
 923int f2fs_map_blocks(struct inode *inode, struct f2fs_map_blocks *map,
 924                                                int create, int flag)
 925{
 926        unsigned int maxblocks = map->m_len;
 927        struct dnode_of_data dn;
 928        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 929        int mode = create ? ALLOC_NODE : LOOKUP_NODE;
 930        pgoff_t pgofs, end_offset, end;
 931        int err = 0, ofs = 1;
 932        unsigned int ofs_in_node, last_ofs_in_node;
 933        blkcnt_t prealloc;
 934        struct extent_info ei = {0,0,0};
 935        block_t blkaddr;
 936        unsigned int start_pgofs;
 937
 938        if (!maxblocks)
 939                return 0;
 940
 941        map->m_len = 0;
 942        map->m_flags = 0;
 943
 944        /* it only supports block size == page size */
 945        pgofs = (pgoff_t)map->m_lblk;
 946        end = pgofs + maxblocks;
 947
 948        if (!create && f2fs_lookup_extent_cache(inode, pgofs, &ei)) {
 949                map->m_pblk = ei.blk + pgofs - ei.fofs;
 950                map->m_len = min((pgoff_t)maxblocks, ei.fofs + ei.len - pgofs);
 951                map->m_flags = F2FS_MAP_MAPPED;
 952                if (map->m_next_extent)
 953                        *map->m_next_extent = pgofs + map->m_len;
 954                goto out;
 955        }
 956
 957next_dnode:
 958        if (create)
 959                __do_map_lock(sbi, flag, true);
 960
 961        /* When reading holes, we need its node page */
 962        set_new_dnode(&dn, inode, NULL, NULL, 0);
 963        err = get_dnode_of_data(&dn, pgofs, mode);
 964        if (err) {
 965                if (flag == F2FS_GET_BLOCK_BMAP)
 966                        map->m_pblk = 0;
 967                if (err == -ENOENT) {
 968                        err = 0;
 969                        if (map->m_next_pgofs)
 970                                *map->m_next_pgofs =
 971                                        get_next_page_offset(&dn, pgofs);
 972                        if (map->m_next_extent)
 973                                *map->m_next_extent =
 974                                        get_next_page_offset(&dn, pgofs);
 975                }
 976                goto unlock_out;
 977        }
 978
 979        start_pgofs = pgofs;
 980        prealloc = 0;
 981        last_ofs_in_node = ofs_in_node = dn.ofs_in_node;
 982        end_offset = ADDRS_PER_PAGE(dn.node_page, inode);
 983
 984next_block:
 985        blkaddr = datablock_addr(dn.inode, dn.node_page, dn.ofs_in_node);
 986
 987        if (blkaddr == NEW_ADDR || blkaddr == NULL_ADDR) {
 988                if (create) {
 989                        if (unlikely(f2fs_cp_error(sbi))) {
 990                                err = -EIO;
 991                                goto sync_out;
 992                        }
 993                        if (flag == F2FS_GET_BLOCK_PRE_AIO) {
 994                                if (blkaddr == NULL_ADDR) {
 995                                        prealloc++;
 996                                        last_ofs_in_node = dn.ofs_in_node;
 997                                }
 998                        } else {
 999                                err = __allocate_data_block(&dn,
1000                                                        map->m_seg_type);
1001                                if (!err)
1002                                        set_inode_flag(inode, FI_APPEND_WRITE);
1003                        }
1004                        if (err)
1005                                goto sync_out;
1006                        map->m_flags |= F2FS_MAP_NEW;
1007                        blkaddr = dn.data_blkaddr;
1008                } else {
1009                        if (flag == F2FS_GET_BLOCK_BMAP) {
1010                                map->m_pblk = 0;
1011                                goto sync_out;
1012                        }
1013                        if (flag == F2FS_GET_BLOCK_PRECACHE)
1014                                goto sync_out;
1015                        if (flag == F2FS_GET_BLOCK_FIEMAP &&
1016                                                blkaddr == NULL_ADDR) {
1017                                if (map->m_next_pgofs)
1018                                        *map->m_next_pgofs = pgofs + 1;
1019                                goto sync_out;
1020                        }
1021                        if (flag != F2FS_GET_BLOCK_FIEMAP) {
1022                                /* for defragment case */
1023                                if (map->m_next_pgofs)
1024                                        *map->m_next_pgofs = pgofs + 1;
1025                                goto sync_out;
1026                        }
1027                }
1028        }
1029
1030        if (flag == F2FS_GET_BLOCK_PRE_AIO)
1031                goto skip;
1032
1033        if (map->m_len == 0) {
1034                /* preallocated unwritten block should be mapped for fiemap. */
1035                if (blkaddr == NEW_ADDR)
1036                        map->m_flags |= F2FS_MAP_UNWRITTEN;
1037                map->m_flags |= F2FS_MAP_MAPPED;
1038
1039                map->m_pblk = blkaddr;
1040                map->m_len = 1;
1041        } else if ((map->m_pblk != NEW_ADDR &&
1042                        blkaddr == (map->m_pblk + ofs)) ||
1043                        (map->m_pblk == NEW_ADDR && blkaddr == NEW_ADDR) ||
1044                        flag == F2FS_GET_BLOCK_PRE_DIO) {
1045                ofs++;
1046                map->m_len++;
1047        } else {
1048                goto sync_out;
1049        }
1050
1051skip:
1052        dn.ofs_in_node++;
1053        pgofs++;
1054
1055        /* preallocate blocks in batch for one dnode page */
1056        if (flag == F2FS_GET_BLOCK_PRE_AIO &&
1057                        (pgofs == end || dn.ofs_in_node == end_offset)) {
1058
1059                dn.ofs_in_node = ofs_in_node;
1060                err = reserve_new_blocks(&dn, prealloc);
1061                if (err)
1062                        goto sync_out;
1063
1064                map->m_len += dn.ofs_in_node - ofs_in_node;
1065                if (prealloc && dn.ofs_in_node != last_ofs_in_node + 1) {
1066                        err = -ENOSPC;
1067                        goto sync_out;
1068                }
1069                dn.ofs_in_node = end_offset;
1070        }
1071
1072        if (pgofs >= end)
1073                goto sync_out;
1074        else if (dn.ofs_in_node < end_offset)
1075                goto next_block;
1076
1077        if (flag == F2FS_GET_BLOCK_PRECACHE) {
1078                if (map->m_flags & F2FS_MAP_MAPPED) {
1079                        unsigned int ofs = start_pgofs - map->m_lblk;
1080
1081                        f2fs_update_extent_cache_range(&dn,
1082                                start_pgofs, map->m_pblk + ofs,
1083                                map->m_len - ofs);
1084                }
1085        }
1086
1087        f2fs_put_dnode(&dn);
1088
1089        if (create) {
1090                __do_map_lock(sbi, flag, false);
1091                f2fs_balance_fs(sbi, dn.node_changed);
1092        }
1093        goto next_dnode;
1094
1095sync_out:
1096        if (flag == F2FS_GET_BLOCK_PRECACHE) {
1097                if (map->m_flags & F2FS_MAP_MAPPED) {
1098                        unsigned int ofs = start_pgofs - map->m_lblk;
1099
1100                        f2fs_update_extent_cache_range(&dn,
1101                                start_pgofs, map->m_pblk + ofs,
1102                                map->m_len - ofs);
1103                }
1104                if (map->m_next_extent)
1105                        *map->m_next_extent = pgofs + 1;
1106        }
1107        f2fs_put_dnode(&dn);
1108unlock_out:
1109        if (create) {
1110                __do_map_lock(sbi, flag, false);
1111                f2fs_balance_fs(sbi, dn.node_changed);
1112        }
1113out:
1114        trace_f2fs_map_blocks(inode, map, err);
1115        return err;
1116}
1117
1118bool f2fs_overwrite_io(struct inode *inode, loff_t pos, size_t len)
1119{
1120        struct f2fs_map_blocks map;
1121        block_t last_lblk;
1122        int err;
1123
1124        if (pos + len > i_size_read(inode))
1125                return false;
1126
1127        map.m_lblk = F2FS_BYTES_TO_BLK(pos);
1128        map.m_next_pgofs = NULL;
1129        map.m_next_extent = NULL;
1130        map.m_seg_type = NO_CHECK_TYPE;
1131        last_lblk = F2FS_BLK_ALIGN(pos + len);
1132
1133        while (map.m_lblk < last_lblk) {
1134                map.m_len = last_lblk - map.m_lblk;
1135                err = f2fs_map_blocks(inode, &map, 0, F2FS_GET_BLOCK_DEFAULT);
1136                if (err || map.m_len == 0)
1137                        return false;
1138                map.m_lblk += map.m_len;
1139        }
1140        return true;
1141}
1142
1143static int __get_data_block(struct inode *inode, sector_t iblock,
1144                        struct buffer_head *bh, int create, int flag,
1145                        pgoff_t *next_pgofs, int seg_type)
1146{
1147        struct f2fs_map_blocks map;
1148        int err;
1149
1150        map.m_lblk = iblock;
1151        map.m_len = bh->b_size >> inode->i_blkbits;
1152        map.m_next_pgofs = next_pgofs;
1153        map.m_next_extent = NULL;
1154        map.m_seg_type = seg_type;
1155
1156        err = f2fs_map_blocks(inode, &map, create, flag);
1157        if (!err) {
1158                map_bh(bh, inode->i_sb, map.m_pblk);
1159                bh->b_state = (bh->b_state & ~F2FS_MAP_FLAGS) | map.m_flags;
1160                bh->b_size = (u64)map.m_len << inode->i_blkbits;
1161        }
1162        return err;
1163}
1164
1165static int get_data_block(struct inode *inode, sector_t iblock,
1166                        struct buffer_head *bh_result, int create, int flag,
1167                        pgoff_t *next_pgofs)
1168{
1169        return __get_data_block(inode, iblock, bh_result, create,
1170                                                        flag, next_pgofs,
1171                                                        NO_CHECK_TYPE);
1172}
1173
1174static int get_data_block_dio(struct inode *inode, sector_t iblock,
1175                        struct buffer_head *bh_result, int create)
1176{
1177        return __get_data_block(inode, iblock, bh_result, create,
1178                                                F2FS_GET_BLOCK_DEFAULT, NULL,
1179                                                rw_hint_to_seg_type(
1180                                                        inode->i_write_hint));
1181}
1182
1183static int get_data_block_bmap(struct inode *inode, sector_t iblock,
1184                        struct buffer_head *bh_result, int create)
1185{
1186        /* Block number less than F2FS MAX BLOCKS */
1187        if (unlikely(iblock >= F2FS_I_SB(inode)->max_file_blocks))
1188                return -EFBIG;
1189
1190        return __get_data_block(inode, iblock, bh_result, create,
1191                                                F2FS_GET_BLOCK_BMAP, NULL,
1192                                                NO_CHECK_TYPE);
1193}
1194
1195static inline sector_t logical_to_blk(struct inode *inode, loff_t offset)
1196{
1197        return (offset >> inode->i_blkbits);
1198}
1199
1200static inline loff_t blk_to_logical(struct inode *inode, sector_t blk)
1201{
1202        return (blk << inode->i_blkbits);
1203}
1204
1205static int f2fs_xattr_fiemap(struct inode *inode,
1206                                struct fiemap_extent_info *fieinfo)
1207{
1208        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1209        struct page *page;
1210        struct node_info ni;
1211        __u64 phys = 0, len;
1212        __u32 flags;
1213        nid_t xnid = F2FS_I(inode)->i_xattr_nid;
1214        int err = 0;
1215
1216        if (f2fs_has_inline_xattr(inode)) {
1217                int offset;
1218
1219                page = f2fs_grab_cache_page(NODE_MAPPING(sbi),
1220                                                inode->i_ino, false);
1221                if (!page)
1222                        return -ENOMEM;
1223
1224                get_node_info(sbi, inode->i_ino, &ni);
1225
1226                phys = (__u64)blk_to_logical(inode, ni.blk_addr);
1227                offset = offsetof(struct f2fs_inode, i_addr) +
1228                                        sizeof(__le32) * (DEF_ADDRS_PER_INODE -
1229                                        get_inline_xattr_addrs(inode));
1230
1231                phys += offset;
1232                len = inline_xattr_size(inode);
1233
1234                f2fs_put_page(page, 1);
1235
1236                flags = FIEMAP_EXTENT_DATA_INLINE | FIEMAP_EXTENT_NOT_ALIGNED;
1237
1238                if (!xnid)
1239                        flags |= FIEMAP_EXTENT_LAST;
1240
1241                err = fiemap_fill_next_extent(fieinfo, 0, phys, len, flags);
1242                if (err || err == 1)
1243                        return err;
1244        }
1245
1246        if (xnid) {
1247                page = f2fs_grab_cache_page(NODE_MAPPING(sbi), xnid, false);
1248                if (!page)
1249                        return -ENOMEM;
1250
1251                get_node_info(sbi, xnid, &ni);
1252
1253                phys = (__u64)blk_to_logical(inode, ni.blk_addr);
1254                len = inode->i_sb->s_blocksize;
1255
1256                f2fs_put_page(page, 1);
1257
1258                flags = FIEMAP_EXTENT_LAST;
1259        }
1260
1261        if (phys)
1262                err = fiemap_fill_next_extent(fieinfo, 0, phys, len, flags);
1263
1264        return (err < 0 ? err : 0);
1265}
1266
1267int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
1268                u64 start, u64 len)
1269{
1270        struct buffer_head map_bh;
1271        sector_t start_blk, last_blk;
1272        pgoff_t next_pgofs;
1273        u64 logical = 0, phys = 0, size = 0;
1274        u32 flags = 0;
1275        int ret = 0;
1276
1277        if (fieinfo->fi_flags & FIEMAP_FLAG_CACHE) {
1278                ret = f2fs_precache_extents(inode);
1279                if (ret)
1280                        return ret;
1281        }
1282
1283        ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR);
1284        if (ret)
1285                return ret;
1286
1287        inode_lock(inode);
1288
1289        if (fieinfo->fi_flags & FIEMAP_FLAG_XATTR) {
1290                ret = f2fs_xattr_fiemap(inode, fieinfo);
1291                goto out;
1292        }
1293
1294        if (f2fs_has_inline_data(inode)) {
1295                ret = f2fs_inline_data_fiemap(inode, fieinfo, start, len);
1296                if (ret != -EAGAIN)
1297                        goto out;
1298        }
1299
1300        if (logical_to_blk(inode, len) == 0)
1301                len = blk_to_logical(inode, 1);
1302
1303        start_blk = logical_to_blk(inode, start);
1304        last_blk = logical_to_blk(inode, start + len - 1);
1305
1306next:
1307        memset(&map_bh, 0, sizeof(struct buffer_head));
1308        map_bh.b_size = len;
1309
1310        ret = get_data_block(inode, start_blk, &map_bh, 0,
1311                                        F2FS_GET_BLOCK_FIEMAP, &next_pgofs);
1312        if (ret)
1313                goto out;
1314
1315        /* HOLE */
1316        if (!buffer_mapped(&map_bh)) {
1317                start_blk = next_pgofs;
1318
1319                if (blk_to_logical(inode, start_blk) < blk_to_logical(inode,
1320                                        F2FS_I_SB(inode)->max_file_blocks))
1321                        goto prep_next;
1322
1323                flags |= FIEMAP_EXTENT_LAST;
1324        }
1325
1326        if (size) {
1327                if (f2fs_encrypted_inode(inode))
1328                        flags |= FIEMAP_EXTENT_DATA_ENCRYPTED;
1329
1330                ret = fiemap_fill_next_extent(fieinfo, logical,
1331                                phys, size, flags);
1332        }
1333
1334        if (start_blk > last_blk || ret)
1335                goto out;
1336
1337        logical = blk_to_logical(inode, start_blk);
1338        phys = blk_to_logical(inode, map_bh.b_blocknr);
1339        size = map_bh.b_size;
1340        flags = 0;
1341        if (buffer_unwritten(&map_bh))
1342                flags = FIEMAP_EXTENT_UNWRITTEN;
1343
1344        start_blk += logical_to_blk(inode, size);
1345
1346prep_next:
1347        cond_resched();
1348        if (fatal_signal_pending(current))
1349                ret = -EINTR;
1350        else
1351                goto next;
1352out:
1353        if (ret == 1)
1354                ret = 0;
1355
1356        inode_unlock(inode);
1357        return ret;
1358}
1359
1360/*
1361 * This function was originally taken from fs/mpage.c, and customized for f2fs.
1362 * Major change was from block_size == page_size in f2fs by default.
1363 */
1364static int f2fs_mpage_readpages(struct address_space *mapping,
1365                        struct list_head *pages, struct page *page,
1366                        unsigned nr_pages)
1367{
1368        struct bio *bio = NULL;
1369        sector_t last_block_in_bio = 0;
1370        struct inode *inode = mapping->host;
1371        const unsigned blkbits = inode->i_blkbits;
1372        const unsigned blocksize = 1 << blkbits;
1373        sector_t block_in_file;
1374        sector_t last_block;
1375        sector_t last_block_in_file;
1376        sector_t block_nr;
1377        struct f2fs_map_blocks map;
1378
1379        map.m_pblk = 0;
1380        map.m_lblk = 0;
1381        map.m_len = 0;
1382        map.m_flags = 0;
1383        map.m_next_pgofs = NULL;
1384        map.m_next_extent = NULL;
1385        map.m_seg_type = NO_CHECK_TYPE;
1386
1387        for (; nr_pages; nr_pages--) {
1388                if (pages) {
1389                        page = list_last_entry(pages, struct page, lru);
1390
1391                        prefetchw(&page->flags);
1392                        list_del(&page->lru);
1393                        if (add_to_page_cache_lru(page, mapping,
1394                                                  page->index,
1395                                                  readahead_gfp_mask(mapping)))
1396                                goto next_page;
1397                }
1398
1399                block_in_file = (sector_t)page->index;
1400                last_block = block_in_file + nr_pages;
1401                last_block_in_file = (i_size_read(inode) + blocksize - 1) >>
1402                                                                blkbits;
1403                if (last_block > last_block_in_file)
1404                        last_block = last_block_in_file;
1405
1406                /*
1407                 * Map blocks using the previous result first.
1408                 */
1409                if ((map.m_flags & F2FS_MAP_MAPPED) &&
1410                                block_in_file > map.m_lblk &&
1411                                block_in_file < (map.m_lblk + map.m_len))
1412                        goto got_it;
1413
1414                /*
1415                 * Then do more f2fs_map_blocks() calls until we are
1416                 * done with this page.
1417                 */
1418                map.m_flags = 0;
1419
1420                if (block_in_file < last_block) {
1421                        map.m_lblk = block_in_file;
1422                        map.m_len = last_block - block_in_file;
1423
1424                        if (f2fs_map_blocks(inode, &map, 0,
1425                                                F2FS_GET_BLOCK_DEFAULT))
1426                                goto set_error_page;
1427                }
1428got_it:
1429                if ((map.m_flags & F2FS_MAP_MAPPED)) {
1430                        block_nr = map.m_pblk + block_in_file - map.m_lblk;
1431                        SetPageMappedToDisk(page);
1432
1433                        if (!PageUptodate(page) && !cleancache_get_page(page)) {
1434                                SetPageUptodate(page);
1435                                goto confused;
1436                        }
1437                } else {
1438                        zero_user_segment(page, 0, PAGE_SIZE);
1439                        if (!PageUptodate(page))
1440                                SetPageUptodate(page);
1441                        unlock_page(page);
1442                        goto next_page;
1443                }
1444
1445                /*
1446                 * This page will go to BIO.  Do we need to send this
1447                 * BIO off first?
1448                 */
1449                if (bio && (last_block_in_bio != block_nr - 1 ||
1450                        !__same_bdev(F2FS_I_SB(inode), block_nr, bio))) {
1451submit_and_realloc:
1452                        __submit_bio(F2FS_I_SB(inode), bio, DATA);
1453                        bio = NULL;
1454                }
1455                if (bio == NULL) {
1456                        bio = f2fs_grab_read_bio(inode, block_nr, nr_pages);
1457                        if (IS_ERR(bio)) {
1458                                bio = NULL;
1459                                goto set_error_page;
1460                        }
1461                }
1462
1463                if (bio_add_page(bio, page, blocksize, 0) < blocksize)
1464                        goto submit_and_realloc;
1465
1466                last_block_in_bio = block_nr;
1467                goto next_page;
1468set_error_page:
1469                SetPageError(page);
1470                zero_user_segment(page, 0, PAGE_SIZE);
1471                unlock_page(page);
1472                goto next_page;
1473confused:
1474                if (bio) {
1475                        __submit_bio(F2FS_I_SB(inode), bio, DATA);
1476                        bio = NULL;
1477                }
1478                unlock_page(page);
1479next_page:
1480                if (pages)
1481                        put_page(page);
1482        }
1483        BUG_ON(pages && !list_empty(pages));
1484        if (bio)
1485                __submit_bio(F2FS_I_SB(inode), bio, DATA);
1486        return 0;
1487}
1488
1489static int f2fs_read_data_page(struct file *file, struct page *page)
1490{
1491        struct inode *inode = page->mapping->host;
1492        int ret = -EAGAIN;
1493
1494        trace_f2fs_readpage(page, DATA);
1495
1496        /* If the file has inline data, try to read it directly */
1497        if (f2fs_has_inline_data(inode))
1498                ret = f2fs_read_inline_data(inode, page);
1499        if (ret == -EAGAIN)
1500                ret = f2fs_mpage_readpages(page->mapping, NULL, page, 1);
1501        return ret;
1502}
1503
1504static int f2fs_read_data_pages(struct file *file,
1505                        struct address_space *mapping,
1506                        struct list_head *pages, unsigned nr_pages)
1507{
1508        struct inode *inode = mapping->host;
1509        struct page *page = list_last_entry(pages, struct page, lru);
1510
1511        trace_f2fs_readpages(inode, page, nr_pages);
1512
1513        /* If the file has inline data, skip readpages */
1514        if (f2fs_has_inline_data(inode))
1515                return 0;
1516
1517        return f2fs_mpage_readpages(mapping, pages, NULL, nr_pages);
1518}
1519
1520static int encrypt_one_page(struct f2fs_io_info *fio)
1521{
1522        struct inode *inode = fio->page->mapping->host;
1523        gfp_t gfp_flags = GFP_NOFS;
1524
1525        if (!f2fs_encrypted_file(inode))
1526                return 0;
1527
1528        /* wait for GCed encrypted page writeback */
1529        f2fs_wait_on_block_writeback(fio->sbi, fio->old_blkaddr);
1530
1531retry_encrypt:
1532        fio->encrypted_page = fscrypt_encrypt_page(inode, fio->page,
1533                        PAGE_SIZE, 0, fio->page->index, gfp_flags);
1534        if (!IS_ERR(fio->encrypted_page))
1535                return 0;
1536
1537        /* flush pending IOs and wait for a while in the ENOMEM case */
1538        if (PTR_ERR(fio->encrypted_page) == -ENOMEM) {
1539                f2fs_flush_merged_writes(fio->sbi);
1540                congestion_wait(BLK_RW_ASYNC, HZ/50);
1541                gfp_flags |= __GFP_NOFAIL;
1542                goto retry_encrypt;
1543        }
1544        return PTR_ERR(fio->encrypted_page);
1545}
1546
1547static inline bool check_inplace_update_policy(struct inode *inode,
1548                                struct f2fs_io_info *fio)
1549{
1550        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1551        unsigned int policy = SM_I(sbi)->ipu_policy;
1552
1553        if (policy & (0x1 << F2FS_IPU_FORCE))
1554                return true;
1555        if (policy & (0x1 << F2FS_IPU_SSR) && need_SSR(sbi))
1556                return true;
1557        if (policy & (0x1 << F2FS_IPU_UTIL) &&
1558                        utilization(sbi) > SM_I(sbi)->min_ipu_util)
1559                return true;
1560        if (policy & (0x1 << F2FS_IPU_SSR_UTIL) && need_SSR(sbi) &&
1561                        utilization(sbi) > SM_I(sbi)->min_ipu_util)
1562                return true;
1563
1564        /*
1565         * IPU for rewrite async pages
1566         */
1567        if (policy & (0x1 << F2FS_IPU_ASYNC) &&
1568                        fio && fio->op == REQ_OP_WRITE &&
1569                        !(fio->op_flags & REQ_SYNC) &&
1570                        !f2fs_encrypted_inode(inode))
1571                return true;
1572
1573        /* this is only set during fdatasync */
1574        if (policy & (0x1 << F2FS_IPU_FSYNC) &&
1575                        is_inode_flag_set(inode, FI_NEED_IPU))
1576                return true;
1577
1578        return false;
1579}
1580
1581bool should_update_inplace(struct inode *inode, struct f2fs_io_info *fio)
1582{
1583        if (f2fs_is_pinned_file(inode))
1584                return true;
1585
1586        /* if this is cold file, we should overwrite to avoid fragmentation */
1587        if (file_is_cold(inode))
1588                return true;
1589
1590        return check_inplace_update_policy(inode, fio);
1591}
1592
1593bool should_update_outplace(struct inode *inode, struct f2fs_io_info *fio)
1594{
1595        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1596
1597        if (test_opt(sbi, LFS))
1598                return true;
1599        if (S_ISDIR(inode->i_mode))
1600                return true;
1601        if (f2fs_is_atomic_file(inode))
1602                return true;
1603        if (fio) {
1604                if (is_cold_data(fio->page))
1605                        return true;
1606                if (IS_ATOMIC_WRITTEN_PAGE(fio->page))
1607                        return true;
1608        }
1609        return false;
1610}
1611
1612static inline bool need_inplace_update(struct f2fs_io_info *fio)
1613{
1614        struct inode *inode = fio->page->mapping->host;
1615
1616        if (should_update_outplace(inode, fio))
1617                return false;
1618
1619        return should_update_inplace(inode, fio);
1620}
1621
1622static inline bool valid_ipu_blkaddr(struct f2fs_io_info *fio)
1623{
1624        if (fio->old_blkaddr == NEW_ADDR)
1625                return false;
1626        if (fio->old_blkaddr == NULL_ADDR)
1627                return false;
1628        return true;
1629}
1630
1631int do_write_data_page(struct f2fs_io_info *fio)
1632{
1633        struct page *page = fio->page;
1634        struct inode *inode = page->mapping->host;
1635        struct dnode_of_data dn;
1636        struct extent_info ei = {0,0,0};
1637        bool ipu_force = false;
1638        int err = 0;
1639
1640        set_new_dnode(&dn, inode, NULL, NULL, 0);
1641        if (need_inplace_update(fio) &&
1642                        f2fs_lookup_extent_cache(inode, page->index, &ei)) {
1643                fio->old_blkaddr = ei.blk + page->index - ei.fofs;
1644
1645                if (valid_ipu_blkaddr(fio)) {
1646                        ipu_force = true;
1647                        fio->need_lock = LOCK_DONE;
1648                        goto got_it;
1649                }
1650        }
1651
1652        /* Deadlock due to between page->lock and f2fs_lock_op */
1653        if (fio->need_lock == LOCK_REQ && !f2fs_trylock_op(fio->sbi))
1654                return -EAGAIN;
1655
1656        err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
1657        if (err)
1658                goto out;
1659
1660        fio->old_blkaddr = dn.data_blkaddr;
1661
1662        /* This page is already truncated */
1663        if (fio->old_blkaddr == NULL_ADDR) {
1664                ClearPageUptodate(page);
1665                goto out_writepage;
1666        }
1667got_it:
1668        /*
1669         * If current allocation needs SSR,
1670         * it had better in-place writes for updated data.
1671         */
1672        if (ipu_force || (valid_ipu_blkaddr(fio) && need_inplace_update(fio))) {
1673                err = encrypt_one_page(fio);
1674                if (err)
1675                        goto out_writepage;
1676
1677                set_page_writeback(page);
1678                f2fs_put_dnode(&dn);
1679                if (fio->need_lock == LOCK_REQ)
1680                        f2fs_unlock_op(fio->sbi);
1681                err = rewrite_data_page(fio);
1682                trace_f2fs_do_write_data_page(fio->page, IPU);
1683                set_inode_flag(inode, FI_UPDATE_WRITE);
1684                return err;
1685        }
1686
1687        if (fio->need_lock == LOCK_RETRY) {
1688                if (!f2fs_trylock_op(fio->sbi)) {
1689                        err = -EAGAIN;
1690                        goto out_writepage;
1691                }
1692                fio->need_lock = LOCK_REQ;
1693        }
1694
1695        err = encrypt_one_page(fio);
1696        if (err)
1697                goto out_writepage;
1698
1699        set_page_writeback(page);
1700
1701        /* LFS mode write path */
1702        write_data_page(&dn, fio);
1703        trace_f2fs_do_write_data_page(page, OPU);
1704        set_inode_flag(inode, FI_APPEND_WRITE);
1705        if (page->index == 0)
1706                set_inode_flag(inode, FI_FIRST_BLOCK_WRITTEN);
1707out_writepage:
1708        f2fs_put_dnode(&dn);
1709out:
1710        if (fio->need_lock == LOCK_REQ)
1711                f2fs_unlock_op(fio->sbi);
1712        return err;
1713}
1714
1715static int __write_data_page(struct page *page, bool *submitted,
1716                                struct writeback_control *wbc,
1717                                enum iostat_type io_type)
1718{
1719        struct inode *inode = page->mapping->host;
1720        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
1721        loff_t i_size = i_size_read(inode);
1722        const pgoff_t end_index = ((unsigned long long) i_size)
1723                                                        >> PAGE_SHIFT;
1724        loff_t psize = (page->index + 1) << PAGE_SHIFT;
1725        unsigned offset = 0;
1726        bool need_balance_fs = false;
1727        int err = 0;
1728        struct f2fs_io_info fio = {
1729                .sbi = sbi,
1730                .ino = inode->i_ino,
1731                .type = DATA,
1732                .op = REQ_OP_WRITE,
1733                .op_flags = wbc_to_write_flags(wbc),
1734                .old_blkaddr = NULL_ADDR,
1735                .page = page,
1736                .encrypted_page = NULL,
1737                .submitted = false,
1738                .need_lock = LOCK_RETRY,
1739                .io_type = io_type,
1740                .io_wbc = wbc,
1741        };
1742
1743        trace_f2fs_writepage(page, DATA);
1744
1745        /* we should bypass data pages to proceed the kworkder jobs */
1746        if (unlikely(f2fs_cp_error(sbi))) {
1747                mapping_set_error(page->mapping, -EIO);
1748                goto out;
1749        }
1750
1751        if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
1752                goto redirty_out;
1753
1754        if (page->index < end_index)
1755                goto write;
1756
1757        /*
1758         * If the offset is out-of-range of file size,
1759         * this page does not have to be written to disk.
1760         */
1761        offset = i_size & (PAGE_SIZE - 1);
1762        if ((page->index >= end_index + 1) || !offset)
1763                goto out;
1764
1765        zero_user_segment(page, offset, PAGE_SIZE);
1766write:
1767        if (f2fs_is_drop_cache(inode))
1768                goto out;
1769        /* we should not write 0'th page having journal header */
1770        if (f2fs_is_volatile_file(inode) && (!page->index ||
1771                        (!wbc->for_reclaim &&
1772                        available_free_memory(sbi, BASE_CHECK))))
1773                goto redirty_out;
1774
1775        /* Dentry blocks are controlled by checkpoint */
1776        if (S_ISDIR(inode->i_mode)) {
1777                fio.need_lock = LOCK_DONE;
1778                err = do_write_data_page(&fio);
1779                goto done;
1780        }
1781
1782        if (!wbc->for_reclaim)
1783                need_balance_fs = true;
1784        else if (has_not_enough_free_secs(sbi, 0, 0))
1785                goto redirty_out;
1786        else
1787                set_inode_flag(inode, FI_HOT_DATA);
1788
1789        err = -EAGAIN;
1790        if (f2fs_has_inline_data(inode)) {
1791                err = f2fs_write_inline_data(inode, page);
1792                if (!err)
1793                        goto out;
1794        }
1795
1796        if (err == -EAGAIN) {
1797                err = do_write_data_page(&fio);
1798                if (err == -EAGAIN) {
1799                        fio.need_lock = LOCK_REQ;
1800                        err = do_write_data_page(&fio);
1801                }
1802        }
1803
1804        if (err) {
1805                file_set_keep_isize(inode);
1806        } else {
1807                down_write(&F2FS_I(inode)->i_sem);
1808                if (F2FS_I(inode)->last_disk_size < psize)
1809                        F2FS_I(inode)->last_disk_size = psize;
1810                up_write(&F2FS_I(inode)->i_sem);
1811        }
1812
1813done:
1814        if (err && err != -ENOENT)
1815                goto redirty_out;
1816
1817out:
1818        inode_dec_dirty_pages(inode);
1819        if (err)
1820                ClearPageUptodate(page);
1821
1822        if (wbc->for_reclaim) {
1823                f2fs_submit_merged_write_cond(sbi, inode, 0, page->index, DATA);
1824                clear_inode_flag(inode, FI_HOT_DATA);
1825                remove_dirty_inode(inode);
1826                submitted = NULL;
1827        }
1828
1829        unlock_page(page);
1830        if (!S_ISDIR(inode->i_mode))
1831                f2fs_balance_fs(sbi, need_balance_fs);
1832
1833        if (unlikely(f2fs_cp_error(sbi))) {
1834                f2fs_submit_merged_write(sbi, DATA);
1835                submitted = NULL;
1836        }
1837
1838        if (submitted)
1839                *submitted = fio.submitted;
1840
1841        return 0;
1842
1843redirty_out:
1844        redirty_page_for_writepage(wbc, page);
1845        if (!err)
1846                return AOP_WRITEPAGE_ACTIVATE;
1847        unlock_page(page);
1848        return err;
1849}
1850
1851static int f2fs_write_data_page(struct page *page,
1852                                        struct writeback_control *wbc)
1853{
1854        return __write_data_page(page, NULL, wbc, FS_DATA_IO);
1855}
1856
1857/*
1858 * This function was copied from write_cche_pages from mm/page-writeback.c.
1859 * The major change is making write step of cold data page separately from
1860 * warm/hot data page.
1861 */
1862static int f2fs_write_cache_pages(struct address_space *mapping,
1863                                        struct writeback_control *wbc,
1864                                        enum iostat_type io_type)
1865{
1866        int ret = 0;
1867        int done = 0;
1868        struct pagevec pvec;
1869        int nr_pages;
1870        pgoff_t uninitialized_var(writeback_index);
1871        pgoff_t index;
1872        pgoff_t end;            /* Inclusive */
1873        pgoff_t done_index;
1874        pgoff_t last_idx = ULONG_MAX;
1875        int cycled;
1876        int range_whole = 0;
1877        int tag;
1878
1879        pagevec_init(&pvec);
1880
1881        if (get_dirty_pages(mapping->host) <=
1882                                SM_I(F2FS_M_SB(mapping))->min_hot_blocks)
1883                set_inode_flag(mapping->host, FI_HOT_DATA);
1884        else
1885                clear_inode_flag(mapping->host, FI_HOT_DATA);
1886
1887        if (wbc->range_cyclic) {
1888                writeback_index = mapping->writeback_index; /* prev offset */
1889                index = writeback_index;
1890                if (index == 0)
1891                        cycled = 1;
1892                else
1893                        cycled = 0;
1894                end = -1;
1895        } else {
1896                index = wbc->range_start >> PAGE_SHIFT;
1897                end = wbc->range_end >> PAGE_SHIFT;
1898                if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
1899                        range_whole = 1;
1900                cycled = 1; /* ignore range_cyclic tests */
1901        }
1902        if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
1903                tag = PAGECACHE_TAG_TOWRITE;
1904        else
1905                tag = PAGECACHE_TAG_DIRTY;
1906retry:
1907        if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages)
1908                tag_pages_for_writeback(mapping, index, end);
1909        done_index = index;
1910        while (!done && (index <= end)) {
1911                int i;
1912
1913                nr_pages = pagevec_lookup_range_tag(&pvec, mapping, &index, end,
1914                                tag);
1915                if (nr_pages == 0)
1916                        break;
1917
1918                for (i = 0; i < nr_pages; i++) {
1919                        struct page *page = pvec.pages[i];
1920                        bool submitted = false;
1921
1922                        done_index = page->index;
1923retry_write:
1924                        lock_page(page);
1925
1926                        if (unlikely(page->mapping != mapping)) {
1927continue_unlock:
1928                                unlock_page(page);
1929                                continue;
1930                        }
1931
1932                        if (!PageDirty(page)) {
1933                                /* someone wrote it for us */
1934                                goto continue_unlock;
1935                        }
1936
1937                        if (PageWriteback(page)) {
1938                                if (wbc->sync_mode != WB_SYNC_NONE)
1939                                        f2fs_wait_on_page_writeback(page,
1940                                                                DATA, true);
1941                                else
1942                                        goto continue_unlock;
1943                        }
1944
1945                        BUG_ON(PageWriteback(page));
1946                        if (!clear_page_dirty_for_io(page))
1947                                goto continue_unlock;
1948
1949                        ret = __write_data_page(page, &submitted, wbc, io_type);
1950                        if (unlikely(ret)) {
1951                                /*
1952                                 * keep nr_to_write, since vfs uses this to
1953                                 * get # of written pages.
1954                                 */
1955                                if (ret == AOP_WRITEPAGE_ACTIVATE) {
1956                                        unlock_page(page);
1957                                        ret = 0;
1958                                        continue;
1959                                } else if (ret == -EAGAIN) {
1960                                        ret = 0;
1961                                        if (wbc->sync_mode == WB_SYNC_ALL) {
1962                                                cond_resched();
1963                                                congestion_wait(BLK_RW_ASYNC,
1964                                                                        HZ/50);
1965                                                goto retry_write;
1966                                        }
1967                                        continue;
1968                                }
1969                                done_index = page->index + 1;
1970                                done = 1;
1971                                break;
1972                        } else if (submitted) {
1973                                last_idx = page->index;
1974                        }
1975
1976                        /* give a priority to WB_SYNC threads */
1977                        if ((atomic_read(&F2FS_M_SB(mapping)->wb_sync_req) ||
1978                                        --wbc->nr_to_write <= 0) &&
1979                                        wbc->sync_mode == WB_SYNC_NONE) {
1980                                done = 1;
1981                                break;
1982                        }
1983                }
1984                pagevec_release(&pvec);
1985                cond_resched();
1986        }
1987
1988        if (!cycled && !done) {
1989                cycled = 1;
1990                index = 0;
1991                end = writeback_index - 1;
1992                goto retry;
1993        }
1994        if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
1995                mapping->writeback_index = done_index;
1996
1997        if (last_idx != ULONG_MAX)
1998                f2fs_submit_merged_write_cond(F2FS_M_SB(mapping), mapping->host,
1999                                                0, last_idx, DATA);
2000
2001        return ret;
2002}
2003
2004int __f2fs_write_data_pages(struct address_space *mapping,
2005                                                struct writeback_control *wbc,
2006                                                enum iostat_type io_type)
2007{
2008        struct inode *inode = mapping->host;
2009        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
2010        struct blk_plug plug;
2011        int ret;
2012
2013        /* deal with chardevs and other special file */
2014        if (!mapping->a_ops->writepage)
2015                return 0;
2016
2017        /* skip writing if there is no dirty page in this inode */
2018        if (!get_dirty_pages(inode) && wbc->sync_mode == WB_SYNC_NONE)
2019                return 0;
2020
2021        /* during POR, we don't need to trigger writepage at all. */
2022        if (unlikely(is_sbi_flag_set(sbi, SBI_POR_DOING)))
2023                goto skip_write;
2024
2025        if (S_ISDIR(inode->i_mode) && wbc->sync_mode == WB_SYNC_NONE &&
2026                        get_dirty_pages(inode) < nr_pages_to_skip(sbi, DATA) &&
2027                        available_free_memory(sbi, DIRTY_DENTS))
2028                goto skip_write;
2029
2030        /* skip writing during file defragment */
2031        if (is_inode_flag_set(inode, FI_DO_DEFRAG))
2032                goto skip_write;
2033
2034        trace_f2fs_writepages(mapping->host, wbc, DATA);
2035
2036        /* to avoid spliting IOs due to mixed WB_SYNC_ALL and WB_SYNC_NONE */
2037        if (wbc->sync_mode == WB_SYNC_ALL)
2038                atomic_inc(&sbi->wb_sync_req);
2039        else if (atomic_read(&sbi->wb_sync_req))
2040                goto skip_write;
2041
2042        blk_start_plug(&plug);
2043        ret = f2fs_write_cache_pages(mapping, wbc, io_type);
2044        blk_finish_plug(&plug);
2045
2046        if (wbc->sync_mode == WB_SYNC_ALL)
2047                atomic_dec(&sbi->wb_sync_req);
2048        /*
2049         * if some pages were truncated, we cannot guarantee its mapping->host
2050         * to detect pending bios.
2051         */
2052
2053        remove_dirty_inode(inode);
2054        return ret;
2055
2056skip_write:
2057        wbc->pages_skipped += get_dirty_pages(inode);
2058        trace_f2fs_writepages(mapping->host, wbc, DATA);
2059        return 0;
2060}
2061
2062static int f2fs_write_data_pages(struct address_space *mapping,
2063                            struct writeback_control *wbc)
2064{
2065        struct inode *inode = mapping->host;
2066
2067        return __f2fs_write_data_pages(mapping, wbc,
2068                        F2FS_I(inode)->cp_task == current ?
2069                        FS_CP_DATA_IO : FS_DATA_IO);
2070}
2071
2072static void f2fs_write_failed(struct address_space *mapping, loff_t to)
2073{
2074        struct inode *inode = mapping->host;
2075        loff_t i_size = i_size_read(inode);
2076
2077        if (to > i_size) {
2078                down_write(&F2FS_I(inode)->i_mmap_sem);
2079                truncate_pagecache(inode, i_size);
2080                truncate_blocks(inode, i_size, true);
2081                up_write(&F2FS_I(inode)->i_mmap_sem);
2082        }
2083}
2084
2085static int prepare_write_begin(struct f2fs_sb_info *sbi,
2086                        struct page *page, loff_t pos, unsigned len,
2087                        block_t *blk_addr, bool *node_changed)
2088{
2089        struct inode *inode = page->mapping->host;
2090        pgoff_t index = page->index;
2091        struct dnode_of_data dn;
2092        struct page *ipage;
2093        bool locked = false;
2094        struct extent_info ei = {0,0,0};
2095        int err = 0;
2096
2097        /*
2098         * we already allocated all the blocks, so we don't need to get
2099         * the block addresses when there is no need to fill the page.
2100         */
2101        if (!f2fs_has_inline_data(inode) && len == PAGE_SIZE &&
2102                        !is_inode_flag_set(inode, FI_NO_PREALLOC))
2103                return 0;
2104
2105        if (f2fs_has_inline_data(inode) ||
2106                        (pos & PAGE_MASK) >= i_size_read(inode)) {
2107                __do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, true);
2108                locked = true;
2109        }
2110restart:
2111        /* check inline_data */
2112        ipage = get_node_page(sbi, inode->i_ino);
2113        if (IS_ERR(ipage)) {
2114                err = PTR_ERR(ipage);
2115                goto unlock_out;
2116        }
2117
2118        set_new_dnode(&dn, inode, ipage, ipage, 0);
2119
2120        if (f2fs_has_inline_data(inode)) {
2121                if (pos + len <= MAX_INLINE_DATA(inode)) {
2122                        read_inline_data(page, ipage);
2123                        set_inode_flag(inode, FI_DATA_EXIST);
2124                        if (inode->i_nlink)
2125                                set_inline_node(ipage);
2126                } else {
2127                        err = f2fs_convert_inline_page(&dn, page);
2128                        if (err)
2129                                goto out;
2130                        if (dn.data_blkaddr == NULL_ADDR)
2131                                err = f2fs_get_block(&dn, index);
2132                }
2133        } else if (locked) {
2134                err = f2fs_get_block(&dn, index);
2135        } else {
2136                if (f2fs_lookup_extent_cache(inode, index, &ei)) {
2137                        dn.data_blkaddr = ei.blk + index - ei.fofs;
2138                } else {
2139                        /* hole case */
2140                        err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
2141                        if (err || dn.data_blkaddr == NULL_ADDR) {
2142                                f2fs_put_dnode(&dn);
2143                                __do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO,
2144                                                                true);
2145                                locked = true;
2146                                goto restart;
2147                        }
2148                }
2149        }
2150
2151        /* convert_inline_page can make node_changed */
2152        *blk_addr = dn.data_blkaddr;
2153        *node_changed = dn.node_changed;
2154out:
2155        f2fs_put_dnode(&dn);
2156unlock_out:
2157        if (locked)
2158                __do_map_lock(sbi, F2FS_GET_BLOCK_PRE_AIO, false);
2159        return err;
2160}
2161
2162static int f2fs_write_begin(struct file *file, struct address_space *mapping,
2163                loff_t pos, unsigned len, unsigned flags,
2164                struct page **pagep, void **fsdata)
2165{
2166        struct inode *inode = mapping->host;
2167        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
2168        struct page *page = NULL;
2169        pgoff_t index = ((unsigned long long) pos) >> PAGE_SHIFT;
2170        bool need_balance = false, drop_atomic = false;
2171        block_t blkaddr = NULL_ADDR;
2172        int err = 0;
2173
2174        trace_f2fs_write_begin(inode, pos, len, flags);
2175
2176        if (f2fs_is_atomic_file(inode) &&
2177                        !available_free_memory(sbi, INMEM_PAGES)) {
2178                err = -ENOMEM;
2179                drop_atomic = true;
2180                goto fail;
2181        }
2182
2183        /*
2184         * We should check this at this moment to avoid deadlock on inode page
2185         * and #0 page. The locking rule for inline_data conversion should be:
2186         * lock_page(page #0) -> lock_page(inode_page)
2187         */
2188        if (index != 0) {
2189                err = f2fs_convert_inline_inode(inode);
2190                if (err)
2191                        goto fail;
2192        }
2193repeat:
2194        /*
2195         * Do not use grab_cache_page_write_begin() to avoid deadlock due to
2196         * wait_for_stable_page. Will wait that below with our IO control.
2197         */
2198        page = f2fs_pagecache_get_page(mapping, index,
2199                                FGP_LOCK | FGP_WRITE | FGP_CREAT, GFP_NOFS);
2200        if (!page) {
2201                err = -ENOMEM;
2202                goto fail;
2203        }
2204
2205        *pagep = page;
2206
2207        err = prepare_write_begin(sbi, page, pos, len,
2208                                        &blkaddr, &need_balance);
2209        if (err)
2210                goto fail;
2211
2212        if (need_balance && has_not_enough_free_secs(sbi, 0, 0)) {
2213                unlock_page(page);
2214                f2fs_balance_fs(sbi, true);
2215                lock_page(page);
2216                if (page->mapping != mapping) {
2217                        /* The page got truncated from under us */
2218                        f2fs_put_page(page, 1);
2219                        goto repeat;
2220                }
2221        }
2222
2223        f2fs_wait_on_page_writeback(page, DATA, false);
2224
2225        /* wait for GCed encrypted page writeback */
2226        if (f2fs_encrypted_file(inode))
2227                f2fs_wait_on_block_writeback(sbi, blkaddr);
2228
2229        if (len == PAGE_SIZE || PageUptodate(page))
2230                return 0;
2231
2232        if (!(pos & (PAGE_SIZE - 1)) && (pos + len) >= i_size_read(inode)) {
2233                zero_user_segment(page, len, PAGE_SIZE);
2234                return 0;
2235        }
2236
2237        if (blkaddr == NEW_ADDR) {
2238                zero_user_segment(page, 0, PAGE_SIZE);
2239                SetPageUptodate(page);
2240        } else {
2241                err = f2fs_submit_page_read(inode, page, blkaddr);
2242                if (err)
2243                        goto fail;
2244
2245                lock_page(page);
2246                if (unlikely(page->mapping != mapping)) {
2247                        f2fs_put_page(page, 1);
2248                        goto repeat;
2249                }
2250                if (unlikely(!PageUptodate(page))) {
2251                        err = -EIO;
2252                        goto fail;
2253                }
2254        }
2255        return 0;
2256
2257fail:
2258        f2fs_put_page(page, 1);
2259        f2fs_write_failed(mapping, pos + len);
2260        if (drop_atomic)
2261                drop_inmem_pages_all(sbi);
2262        return err;
2263}
2264
2265static int f2fs_write_end(struct file *file,
2266                        struct address_space *mapping,
2267                        loff_t pos, unsigned len, unsigned copied,
2268                        struct page *page, void *fsdata)
2269{
2270        struct inode *inode = page->mapping->host;
2271
2272        trace_f2fs_write_end(inode, pos, len, copied);
2273
2274        /*
2275         * This should be come from len == PAGE_SIZE, and we expect copied
2276         * should be PAGE_SIZE. Otherwise, we treat it with zero copied and
2277         * let generic_perform_write() try to copy data again through copied=0.
2278         */
2279        if (!PageUptodate(page)) {
2280                if (unlikely(copied != len))
2281                        copied = 0;
2282                else
2283                        SetPageUptodate(page);
2284        }
2285        if (!copied)
2286                goto unlock_out;
2287
2288        set_page_dirty(page);
2289
2290        if (pos + copied > i_size_read(inode))
2291                f2fs_i_size_write(inode, pos + copied);
2292unlock_out:
2293        f2fs_put_page(page, 1);
2294        f2fs_update_time(F2FS_I_SB(inode), REQ_TIME);
2295        return copied;
2296}
2297
2298static int check_direct_IO(struct inode *inode, struct iov_iter *iter,
2299                           loff_t offset)
2300{
2301        unsigned blocksize_mask = inode->i_sb->s_blocksize - 1;
2302
2303        if (offset & blocksize_mask)
2304                return -EINVAL;
2305
2306        if (iov_iter_alignment(iter) & blocksize_mask)
2307                return -EINVAL;
2308
2309        return 0;
2310}
2311
2312static ssize_t f2fs_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
2313{
2314        struct address_space *mapping = iocb->ki_filp->f_mapping;
2315        struct inode *inode = mapping->host;
2316        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
2317        size_t count = iov_iter_count(iter);
2318        loff_t offset = iocb->ki_pos;
2319        int rw = iov_iter_rw(iter);
2320        int err;
2321        enum rw_hint hint = iocb->ki_hint;
2322        int whint_mode = F2FS_OPTION(sbi).whint_mode;
2323
2324        err = check_direct_IO(inode, iter, offset);
2325        if (err)
2326                return err;
2327
2328        if (f2fs_force_buffered_io(inode, rw))
2329                return 0;
2330
2331        trace_f2fs_direct_IO_enter(inode, offset, count, rw);
2332
2333        if (rw == WRITE && whint_mode == WHINT_MODE_OFF)
2334                iocb->ki_hint = WRITE_LIFE_NOT_SET;
2335
2336        if (!down_read_trylock(&F2FS_I(inode)->dio_rwsem[rw])) {
2337                if (iocb->ki_flags & IOCB_NOWAIT) {
2338                        iocb->ki_hint = hint;
2339                        err = -EAGAIN;
2340                        goto out;
2341                }
2342                down_read(&F2FS_I(inode)->dio_rwsem[rw]);
2343        }
2344
2345        err = blockdev_direct_IO(iocb, inode, iter, get_data_block_dio);
2346        up_read(&F2FS_I(inode)->dio_rwsem[rw]);
2347
2348        if (rw == WRITE) {
2349                if (whint_mode == WHINT_MODE_OFF)
2350                        iocb->ki_hint = hint;
2351                if (err > 0) {
2352                        f2fs_update_iostat(F2FS_I_SB(inode), APP_DIRECT_IO,
2353                                                                        err);
2354                        set_inode_flag(inode, FI_UPDATE_WRITE);
2355                } else if (err < 0) {
2356                        f2fs_write_failed(mapping, offset + count);
2357                }
2358        }
2359
2360out:
2361        trace_f2fs_direct_IO_exit(inode, offset, count, rw, err);
2362
2363        return err;
2364}
2365
2366void f2fs_invalidate_page(struct page *page, unsigned int offset,
2367                                                        unsigned int length)
2368{
2369        struct inode *inode = page->mapping->host;
2370        struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
2371
2372        if (inode->i_ino >= F2FS_ROOT_INO(sbi) &&
2373                (offset % PAGE_SIZE || length != PAGE_SIZE))
2374                return;
2375
2376        if (PageDirty(page)) {
2377                if (inode->i_ino == F2FS_META_INO(sbi)) {
2378                        dec_page_count(sbi, F2FS_DIRTY_META);
2379                } else if (inode->i_ino == F2FS_NODE_INO(sbi)) {
2380                        dec_page_count(sbi, F2FS_DIRTY_NODES);
2381                } else {
2382                        inode_dec_dirty_pages(inode);
2383                        remove_dirty_inode(inode);
2384                }
2385        }
2386
2387        /* This is atomic written page, keep Private */
2388        if (IS_ATOMIC_WRITTEN_PAGE(page))
2389                return drop_inmem_page(inode, page);
2390
2391        set_page_private(page, 0);
2392        ClearPagePrivate(page);
2393}
2394
2395int f2fs_release_page(struct page *page, gfp_t wait)
2396{
2397        /* If this is dirty page, keep PagePrivate */
2398        if (PageDirty(page))
2399                return 0;
2400
2401        /* This is atomic written page, keep Private */
2402        if (IS_ATOMIC_WRITTEN_PAGE(page))
2403                return 0;
2404
2405        set_page_private(page, 0);
2406        ClearPagePrivate(page);
2407        return 1;
2408}
2409
2410/*
2411 * This was copied from __set_page_dirty_buffers which gives higher performance
2412 * in very high speed storages. (e.g., pmem)
2413 */
2414void f2fs_set_page_dirty_nobuffers(struct page *page)
2415{
2416        struct address_space *mapping = page->mapping;
2417        unsigned long flags;
2418
2419        if (unlikely(!mapping))
2420                return;
2421
2422        spin_lock(&mapping->private_lock);
2423        lock_page_memcg(page);
2424        SetPageDirty(page);
2425        spin_unlock(&mapping->private_lock);
2426
2427        xa_lock_irqsave(&mapping->i_pages, flags);
2428        WARN_ON_ONCE(!PageUptodate(page));
2429        account_page_dirtied(page, mapping);
2430        radix_tree_tag_set(&mapping->i_pages,
2431                        page_index(page), PAGECACHE_TAG_DIRTY);
2432        xa_unlock_irqrestore(&mapping->i_pages, flags);
2433        unlock_page_memcg(page);
2434
2435        __mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
2436        return;
2437}
2438
2439static int f2fs_set_data_page_dirty(struct page *page)
2440{
2441        struct address_space *mapping = page->mapping;
2442        struct inode *inode = mapping->host;
2443
2444        trace_f2fs_set_page_dirty(page, DATA);
2445
2446        if (!PageUptodate(page))
2447                SetPageUptodate(page);
2448
2449        if (f2fs_is_atomic_file(inode) && !f2fs_is_commit_atomic_write(inode)) {
2450                if (!IS_ATOMIC_WRITTEN_PAGE(page)) {
2451                        register_inmem_page(inode, page);
2452                        return 1;
2453                }
2454                /*
2455                 * Previously, this page has been registered, we just
2456                 * return here.
2457                 */
2458                return 0;
2459        }
2460
2461        if (!PageDirty(page)) {
2462                f2fs_set_page_dirty_nobuffers(page);
2463                update_dirty_page(inode, page);
2464                return 1;
2465        }
2466        return 0;
2467}
2468
2469static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
2470{
2471        struct inode *inode = mapping->host;
2472
2473        if (f2fs_has_inline_data(inode))
2474                return 0;
2475
2476        /* make sure allocating whole blocks */
2477        if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
2478                filemap_write_and_wait(mapping);
2479
2480        return generic_block_bmap(mapping, block, get_data_block_bmap);
2481}
2482
2483#ifdef CONFIG_MIGRATION
2484#include <linux/migrate.h>
2485
2486int f2fs_migrate_page(struct address_space *mapping,
2487                struct page *newpage, struct page *page, enum migrate_mode mode)
2488{
2489        int rc, extra_count;
2490        struct f2fs_inode_info *fi = F2FS_I(mapping->host);
2491        bool atomic_written = IS_ATOMIC_WRITTEN_PAGE(page);
2492
2493        BUG_ON(PageWriteback(page));
2494
2495        /* migrating an atomic written page is safe with the inmem_lock hold */
2496        if (atomic_written) {
2497                if (mode != MIGRATE_SYNC)
2498                        return -EBUSY;
2499                if (!mutex_trylock(&fi->inmem_lock))
2500                        return -EAGAIN;
2501        }
2502
2503        /*
2504         * A reference is expected if PagePrivate set when move mapping,
2505         * however F2FS breaks this for maintaining dirty page counts when
2506         * truncating pages. So here adjusting the 'extra_count' make it work.
2507         */
2508        extra_count = (atomic_written ? 1 : 0) - page_has_private(page);
2509        rc = migrate_page_move_mapping(mapping, newpage,
2510                                page, NULL, mode, extra_count);
2511        if (rc != MIGRATEPAGE_SUCCESS) {
2512                if (atomic_written)
2513                        mutex_unlock(&fi->inmem_lock);
2514                return rc;
2515        }
2516
2517        if (atomic_written) {
2518                struct inmem_pages *cur;
2519                list_for_each_entry(cur, &fi->inmem_pages, list)
2520                        if (cur->page == page) {
2521                                cur->page = newpage;
2522                                break;
2523                        }
2524                mutex_unlock(&fi->inmem_lock);
2525                put_page(page);
2526                get_page(newpage);
2527        }
2528
2529        if (PagePrivate(page))
2530                SetPagePrivate(newpage);
2531        set_page_private(newpage, page_private(page));
2532
2533        if (mode != MIGRATE_SYNC_NO_COPY)
2534                migrate_page_copy(newpage, page);
2535        else
2536                migrate_page_states(newpage, page);
2537
2538        return MIGRATEPAGE_SUCCESS;
2539}
2540#endif
2541
2542const struct address_space_operations f2fs_dblock_aops = {
2543        .readpage       = f2fs_read_data_page,
2544        .readpages      = f2fs_read_data_pages,
2545        .writepage      = f2fs_write_data_page,
2546        .writepages     = f2fs_write_data_pages,
2547        .write_begin    = f2fs_write_begin,
2548        .write_end      = f2fs_write_end,
2549        .set_page_dirty = f2fs_set_data_page_dirty,
2550        .invalidatepage = f2fs_invalidate_page,
2551        .releasepage    = f2fs_release_page,
2552        .direct_IO      = f2fs_direct_IO,
2553        .bmap           = f2fs_bmap,
2554#ifdef CONFIG_MIGRATION
2555        .migratepage    = f2fs_migrate_page,
2556#endif
2557};
2558